diff --git a/src/index.js b/src/index.js
index 0004db50..81024bda 100644
--- a/src/index.js
+++ b/src/index.js
@@ -18,7 +18,7 @@ export { Transaction, transact, cleanupYTextFormatting } from './utils/Transacti
 export { UndoManager, undoContentIds } from './utils/UndoManager.js'
 export { logUpdate, logUpdateV2, decodeUpdate, decodeUpdateV2, encodeStateVectorFromUpdate, encodeStateVectorFromUpdateV2, convertUpdateFormatV1ToV2, convertUpdateFormatV2ToV1, obfuscateUpdate, obfuscateUpdateV2, createContentIdsFromUpdate, createContentIdsFromUpdateV2, intersectUpdateWithContentIds, intersectUpdateWithContentIdsV2 } from './utils/updates.js'
 export { YEvent, getPathTo } from './utils/YEvent.js'
-export { TwosetRenderer, baseRenderer, AbstractRenderer, createDiffRenderer, DiffRenderer, createSnapshotRenderer, SnapshotRenderer, Attributions, $renderer } from './utils/Renderer.js'
+export { AttributionsRenderer, createAttributionsRenderer, AbstractRenderer, createDiffRenderer, DiffRenderer, createSnapshotRenderer, SnapshotRenderer, $renderer } from './utils/Renderer.js'
 export { diffDocsToDelta } from './utils/delta-helpers.js'
 export { YType as Type, getTypeChildren, typeMapGetSnapshot, typeMapGetAllSnapshot, $ytype, $ytypeAny } from './ytype.js'
 export { AbstractStruct } from './structs/AbstractStruct.js'
diff --git a/src/utils/Renderer.js b/src/utils/Renderer.js
index 1760bc82..c089ee13 100644
--- a/src/utils/Renderer.js
+++ b/src/utils/Renderer.js
@@ -13,28 +13,87 @@ import { UndoManager, StackItem } from './UndoManager.js'
 
 import { $renderer, AttributedContent } from './renderer-helpers.js'
 
-export { baseRenderer, AbstractRenderer, rendererContentLength, $renderer } from './renderer-helpers.js'
+export { AbstractRenderer, rendererContentLength, $renderer } from './renderer-helpers.js'
 
 /**
+ * Emit a single content piece into `contents`, applying the rendering rules of
+ * {@link AttributionsRenderer}. `inRC` is whether the piece is in `renderedContent` (renders normally,
+ * even when the item is deleted — a "restore"); `attrs` is its attribution (or `null`).
+ *
+ * @param {Array<AttributedContent<any>>} contents - where to write the result
+ * @param {AbstractContent} c
+ * @param {number} clock
+ * @param {boolean} deleted - the item's doc deleted flag
+ * @param {boolean} inRC - whether this piece is in `renderedContent`
+ * @param {Array<ContentAttribute<any>>|null} attrs
+ * @param {0|1|2|3} shouldRender - see {@link AbstractRenderer#readContent}
+ */
+const pushAttributedPiece = (contents, c, clock, deleted, inRC, attrs, shouldRender) => {
+  if (inRC || attrs != null) {
+    // Visible: rendered normally (in `renderedContent`) and/or attributed. A restored deletion
+    // (`inRC`) renders as alive, so its effective `deleted` flag is cleared.
+    contents.push(new AttributedContent(c, clock, deleted && !inRC, attrs, shouldRender))
+  } else if (deleted && shouldRender !== 0 && shouldRender !== 3) {
+    // Genuinely deleted, unattributed, not restored: preserve the legacy retain/delete-op
+    // behavior (mode 3 renders unattributed deleted content as nothing — see DiffRenderer).
+    contents.push(new AttributedContent(c, clock, true, null, shouldRender))
+  }
+  // else: hidden alive content (or invisible deleted content under mode 0/3) — emit nothing.
+}
+
+/**
+ * Renders content with attributions, given a single `attributions` {@link ContentMap} of how to
+ * attribute content and an optional `renderedContent` {@link IdSet} of what renders.
+ *
+ * - `attributions` (inserts ∪ deletes) is merged into a single `renderAs` map; content it covers
+ *   always renders, carrying its attribution.
+ * - `renderedContent` defines the content that renders *normally* — even if the item is marked
+ *   deleted in the doc (a "restore"). It defaults to the doc's alive content (`inserts − deletes`),
+ *   applied implicitly (a piece is in the default set ⟺ its item is not `deleted`), so the common
+ *   "pure attribution overlay" case does no extra work. When a custom set is supplied it is
+ *   authoritative: alive content omitted from it (and unattributed) is hidden.
+ *
+ * Restoring deleted content requires `gc: false` on the doc (the renderer does not rehydrate
+ * garbage-collected content, unlike {@link DiffRenderer}).
+ *
  * @implements AbstractRenderer
  *
  * @extends {ObservableV2<{change:(idset:IdSet,origin:any,local:boolean)=>void}>}
  */
-export class TwosetRenderer extends ObservableV2 {
+export class AttributionsRenderer extends ObservableV2 {
   /**
-   * @param {IdMap<any>} inserts
-   * @param {IdMap<any>} deletes
+   * @param {ContentMap} attributions - how to attribute content (`{ inserts, deletes }` IdMaps)
+   * @param {Object} [options]
+   * @param {IdSet?} [options.renderedContent] - content that renders normally; defaults to the
+   * doc's alive content (`inserts − deletes`), applied implicitly.
    */
-  constructor (inserts, deletes) {
+  constructor (attributions, { renderedContent = null } = {}) {
     super()
-    this.inserts = inserts
-    this.deletes = deletes
     /**
-     * Raw coverage of the two maps — `readContent` remains authoritative for what actually
-     * renders. See {@link AbstractRenderer#attributed}.
+     * The two attribution maps merged into one — `readContent` consults this for how to attribute
+     * a piece.
+     * @type {IdMap<any>}
+     */
+    this.renderAs = mergeIdMaps([attributions.inserts, attributions.deletes])
+    /**
+     * Coverage of `renderAs` (ids that carry attributions). The small set `hasItem` checks. May
+     * over-approximate what actually renders — `readContent` remains authoritative. See
+     * {@link AbstractRenderer#attributed}.
      * @type {IdSet}
      */
-    this.attributed = mergeIdSets([createIdSetFromIdMap(inserts), createIdSetFromIdMap(deletes)])
+    this.attributed = createIdSetFromIdMap(this.renderAs)
+    /**
+     * Custom "content that renders normally" set, or `null` to use the implicit default
+     * (alive ⟺ `!item.deleted`).
+     * @type {IdSet?}
+     */
+    this.renderedContent = renderedContent
+    /**
+     * Union of `renderedContent` and `attributed` — the single cheap "does this produce visible
+     * output?" set. Only materialized when a custom `renderedContent` is supplied.
+     * @type {IdSet?}
+     */
+    this.rendered = renderedContent === null ? null : mergeIdSets([renderedContent, this.attributed])
   }
 
   get $type () { return $renderer }
@@ -44,7 +103,14 @@ export class TwosetRenderer extends ObservableV2 {
    * @return {boolean}
    */
   hasItem (item) {
-    return this.attributed.intersects(item.id.client, item.id.clock, item.length)
+    const { client, clock } = item.id
+    if (this.attributed.intersects(client, clock, item.length)) return true
+    if (this.renderedContent === null) return false
+    // Custom renderedContent differs from the generic fast path for: deleted content that must be
+    // restored, and alive content that must be hidden (not fully covered).
+    return item.deleted
+      ? this.renderedContent.intersects(client, clock, item.length)
+      : !this.renderedContent.covers(client, clock, item.length)
   }
 
   /**
@@ -56,18 +122,49 @@ export class TwosetRenderer extends ObservableV2 {
    * @param {0|1|2|3} shouldRender - whether this should render or just result in a `retain` operation (see AbstractRenderer#readContent)
    */
   readContent (contents, client, clock, deleted, content, shouldRender) {
-    const slice = (deleted ? this.deletes : this.inserts).slice(client, clock, content.getLength())
-    content = slice.length === 1 ? content : content.copy()
-    slice.forEach(s => {
-      const c = content
-      if (s.len < c.getLength()) {
-        content = c.splice(s.len)
+    const total = content.getLength()
+    /**
+     * Segments of the item partitioned by `renderedContent`, or `null` when `inRC` is uniform over
+     * the whole item (the common case: default set, or a custom set that fully contains/excludes
+     * the item). `null` lets us slice `renderAs` once.
+     * @type {Array<import('./ids.js').MaybeIdRange>?}
+     */
+    let outer = null
+    let inRC = !deleted // implicit default: alive ⟺ rendered normally
+    if (this.renderedContent !== null) {
+      outer = this.renderedContent.slice(client, clock, total)
+      if (outer.length === 1) {
+        inRC = outer[0].exists
+        outer = null
       }
-      // see DiffRenderer#readContent: mode 3 renders unattributed deleted content as nothing
-      if (!deleted || s.attrs != null || (shouldRender !== 0 && shouldRender !== 3)) {
-        contents.push(new AttributedContent(c, s.clock, deleted, s.attrs, shouldRender))
+    }
+    if (outer === null) {
+      // Uniform `inRC` — a single `renderAs` slice fixes the attribution boundaries.
+      const slice = this.renderAs.slice(client, clock, total)
+      let rest = slice.length === 1 ? content : content.copy()
+      for (let i = 0; i < slice.length; i++) {
+        const s = slice[i]
+        const c = rest
+        if (i < slice.length - 1) rest = c.splice(s.len)
+        pushAttributedPiece(contents, c, s.clock, deleted, inRC, s.attrs, shouldRender)
       }
-    })
+      return
+    }
+    // General case: partition by `renderedContent` (outer, fixes `inRC`/effectiveDeleted), then by
+    // `renderAs` (inner, fixes attrs). Multiple outer segments ⇒ multi-id (string-like) content, so
+    // copying to avoid mutating the caller's content is safe.
+    let rest = content.copy()
+    for (let oi = 0; oi < outer.length; oi++) {
+      const rcSeg = outer[oi]
+      const slice = this.renderAs.slice(client, rcSeg.clock, rcSeg.len)
+      for (let ii = 0; ii < slice.length; ii++) {
+        const s = slice[ii]
+        const last = oi === outer.length - 1 && ii === slice.length - 1
+        const c = rest
+        if (!last) rest = c.splice(s.len)
+        pushAttributedPiece(contents, c, s.clock, deleted, rcSeg.exists, s.attrs, shouldRender)
+      }
+    }
   }
 
   /**
@@ -77,14 +174,25 @@ export class TwosetRenderer extends ObservableV2 {
   contentLength (item) {
     if (!item.content.isCountable()) {
       return 0
-    } else if (!item.deleted) {
-      return item.length
-    } else {
-      return this.deletes.sliceId(item.id, item.length).reduce((len, s) => s.attrs != null ? len + s.len : len, 0)
     }
+    const { client, clock } = item.id
+    if (this.renderedContent === null) {
+      // Default: alive content renders in full; deleted content only where attributed.
+      return item.deleted ? this.renderAs.coveredLength(client, clock, item.length) : item.length
+    }
+    // Custom: rendered length is |item ∩ rendered| (renderedContent ∪ attributed).
+    return /** @type {IdSet} */ (this.rendered).coveredLength(client, clock, item.length)
   }
 }
 
+/**
+ * @param {ContentMap} attributions - how to attribute content (`{ inserts, deletes }` IdMaps)
+ * @param {Object} [options]
+ * @param {IdSet?} [options.renderedContent] - content that renders normally; defaults to the doc's
+ * alive content (`inserts − deletes`).
+ */
+export const createAttributionsRenderer = (attributions, options) => new AttributionsRenderer(attributions, options)
+
 /**
  * @param {StructStore} store
  * @param {number} client
@@ -197,13 +305,6 @@ const collectSuggestedChanges = (tr, renderer, start, end, collectAll) => {
   return { inserts, deletes }
 }
 
-export class Attributions {
-  constructor () {
-    this.inserts = createIdMap()
-    this.deletes = createIdMap()
-  }
-}
-
 /**
  * @param {IdMap<any>|undefined} attrs
  * @param {IdSet} slice
@@ -221,9 +322,9 @@ export class DiffRenderer extends ObservableV2 {
    * @param {Doc} prevDoc
    * @param {Doc} nextDoc
    * @param {Object} [options] - options for the renderer
-   * @param {Attributions?} [options.attrs] - the attributes to apply to the diff
+   * @param {ContentMap?} [options.attributions] - the attributions to apply to the diff
    */
-  constructor (prevDoc, nextDoc, { attrs = null } = {}) {
+  constructor (prevDoc, nextDoc, { attributions = null } = {}) {
     super()
     const _nextDocInserts = createInsertSetFromStructStore(nextDoc.store, false) // unmaintained
     const _prevDocInserts = createInsertSetFromStructStore(prevDoc.store, false) // unmaintained
@@ -231,8 +332,8 @@ export class DiffRenderer extends ObservableV2 {
     const prevDocDeletes = createDeleteSetFromStructStore(prevDoc.store) // maintained
     const insertDiff = diffIdSet(_nextDocInserts, _prevDocInserts)
     const deleteDiff = diffIdSet(nextDocDeletes, prevDocDeletes)
-    this.inserts = extractAttributions(attrs?.inserts, insertDiff)
-    this.deletes = extractAttributions(attrs?.deletes, deleteDiff)
+    this.inserts = extractAttributions(attributions?.inserts, insertDiff)
+    this.deletes = extractAttributions(attributions?.deletes, deleteDiff)
     /**
      * Raw coverage of `inserts` ∪ `deletes`, maintained alongside them. Over-approximates the
      * actually-rendered set (e.g. it keeps suggested-inserts that were deleted later) —
@@ -247,10 +348,10 @@ export class DiffRenderer extends ObservableV2 {
     this._nextBOH = nextDoc.on('beforeObserverCalls', tr => {
       // update inserts
       const diffInserts = diffIdSet(tr.insertSet, _prevDocInserts)
-      insertIntoIdMap(this.inserts, extractAttributions(attrs?.inserts, diffInserts))
+      insertIntoIdMap(this.inserts, extractAttributions(attributions?.inserts, diffInserts))
       // update deletes
       const diffDeletes = diffIdSet(diffIdSet(tr.deleteSet, prevDocDeletes), this.inserts)
-      insertIntoIdMap(this.deletes, extractAttributions(attrs?.deletes, diffDeletes))
+      insertIntoIdMap(this.deletes, extractAttributions(attributions?.deletes, diffDeletes))
       insertIntoIdSet(this.attributed, diffInserts)
       insertIntoIdSet(this.attributed, diffDeletes)
       // @todo fire update ranges on `diffInserts` and `diffDeletes`
@@ -458,7 +559,7 @@ export class DiffRenderer extends ObservableV2 {
  * @param {Doc} prevDoc
  * @param {Doc} nextDoc
  * @param {Object} [options] - options for the renderer
- * @param {ContentMap?} [options.attrs] - the attributes to apply to the diff
+ * @param {ContentMap?} [options.attributions] - the attributions to apply to the diff
  */
 export const createDiffRenderer = (prevDoc, nextDoc, options) => new DiffRenderer(prevDoc, nextDoc, options)
 
diff --git a/src/utils/ids.js b/src/utils/ids.js
index dd5ac7b3..5ac29ce6 100644
--- a/src/utils/ids.js
+++ b/src/utils/ids.js
@@ -229,6 +229,60 @@ export class IdSet {
     return false
   }
 
+  /**
+   * Whether the entire range `[clock, clock+len)` of `client` is contained in this set.
+   * Allocation-free (binary search). Because `getIds()` returns maximal, merged ranges, full
+   * coverage of a range implies it lies within a single range.
+   *
+   * @param {number} client
+   * @param {number} clock
+   * @param {number} len
+   * @return {boolean}
+   */
+  covers (client, clock, len) {
+    const dr = this.clients.get(client)
+    if (dr) {
+      const ranges = dr.getIds()
+      const index = findIndexInIdRanges(ranges, clock)
+      if (index !== null) {
+        const r = ranges[index]
+        return clock + len <= r.clock + r.len
+      }
+    }
+    return false
+  }
+
+  /**
+   * Total number of ids in `[clock, clock+len)` of `client` contained in this set.
+   * Allocation-free (binary search + linear scan of the overlapping ranges). Equivalent to
+   * `slice(client, clock, len).reduce((s, r) => r.exists ? s + r.len : s, 0)` without allocating.
+   *
+   * @param {number} client
+   * @param {number} clock
+   * @param {number} len
+   * @return {number}
+   */
+  coveredLength (client, clock, len) {
+    const dr = this.clients.get(client)
+    let covered = 0
+    if (dr) {
+      const ranges = dr.getIds()
+      const end = clock + len
+      let index = findRangeStartInIdRanges(ranges, clock)
+      if (index !== null) {
+        for (; index < ranges.length; index++) {
+          const r = ranges[index]
+          if (r.clock >= end) break
+          const from = r.clock < clock ? clock : r.clock
+          const rEnd = r.clock + r.len
+          const to = rEnd > end ? end : rEnd
+          covered += to - from
+        }
+      }
+    }
+    return covered
+  }
+
   /**
    * Return slices of ids that exist in this idset.
    *
@@ -1148,6 +1202,38 @@ export class IdMap {
     return false
   }
 
+  /**
+   * Total number of ids in `[clock, clock+len)` of `client` contained in this map (i.e. carrying
+   * an attribution, incl. an empty `[]`). Allocation-free (binary search + linear scan).
+   * Equivalent to `slice(client, clock, len).reduce((s, r) => r.attrs != null ? s + r.len : s, 0)`
+   * without allocating.
+   *
+   * @param {number} client
+   * @param {number} clock
+   * @param {number} len
+   * @return {number}
+   */
+  coveredLength (client, clock, len) {
+    const dr = this.clients.get(client)
+    let covered = 0
+    if (dr) {
+      const ranges = dr.getIds()
+      const end = clock + len
+      let index = findRangeStartInIdRanges(ranges, clock)
+      if (index !== null) {
+        for (; index < ranges.length; index++) {
+          const r = ranges[index]
+          if (r.clock >= end) break
+          const from = r.clock < clock ? clock : r.clock
+          const rEnd = r.clock + r.len
+          const to = rEnd > end ? end : rEnd
+          covered += to - from
+        }
+      }
+    }
+    return covered
+  }
+
   /**
    * Return attributions for a slice of ids.
    *
diff --git a/src/utils/meta.js b/src/utils/meta.js
index dd9a3b5d..2d6b0d4f 100644
--- a/src/utils/meta.js
+++ b/src/utils/meta.js
@@ -11,6 +11,7 @@ import {
   diffIdMap,
   mergeIdMaps,
   createIdSet,
+  createIdMap,
   mergeIdSets,
   diffIdSet,
   createIdMapFromIdSet,
@@ -88,11 +89,11 @@ export const mergeContentIds = contents => createContentIds(
 )
 
 /**
- * @param {IdMap<any>} inserts
- * @param {IdMap<any>} deletes
+ * @param {IdMap<any>} [inserts]
+ * @param {IdMap<any>} [deletes]
  * @return {ContentMap}
  */
-export const createContentMap = (inserts, deletes) => ({ inserts, deletes })
+export const createContentMap = (inserts = createIdMap(), deletes = createIdMap()) => ({ inserts, deletes })
 
 /**
  * @param {ContentIds} contentIds
diff --git a/src/utils/renderer-helpers.js b/src/utils/renderer-helpers.js
index ee4f8573..6ab93e2a 100644
--- a/src/utils/renderer-helpers.js
+++ b/src/utils/renderer-helpers.js
@@ -109,16 +109,6 @@ export class AbstractRenderer extends ObservableV2 {
 
 export const $renderer = AbstractRenderer.prototype.$type = s.$type('y:r', AbstractRenderer)
 
-/**
- * The absence of a renderer: content renders as-is via the generic fast path, without any
- * attribution lookups.
- *
- * @deprecated pass `null` (or omit the renderer option) instead — kept as an alias for downstream
- * code that referenced the former base-renderer object.
- * @type {null}
- */
-export const baseRenderer = null
-
 /**
  * Rendered length of `item` under `renderer`: the generic rule — alive countable content renders
  * at full length, everything else at length `0` — unless the renderer claims the item.
diff --git a/tests/IdSet.tests.js b/tests/IdSet.tests.js
index 6146baf4..802b1090 100644
--- a/tests/IdSet.tests.js
+++ b/tests/IdSet.tests.js
@@ -242,6 +242,35 @@ export const testRepeatRandomIntersects = tc => {
   compareIdSets(diffed1, altDiffed1)
 }
 
+/**
+ * The allocation-free `covers` / `coveredLength` must agree with per-id `has` and with the
+ * allocating `slice(...)` reduction.
+ *
+ * @param {t.TestCase} tc
+ */
+export const testRepeatRandomCoversAndCoveredLength = tc => {
+  const clients = 4
+  const clockRange = 100
+  const ids = createRandomIdSet(tc.prng, clients, clockRange)
+  for (let iter = 0; iter < 300; iter++) {
+    const client = prng.int31(tc.prng, 0, clients - 1)
+    const clock = prng.int31(tc.prng, 0, clockRange)
+    const len = prng.int31(tc.prng, 1, clockRange - clock + 5) // may exceed the range to cover edges
+    // reference by scanning every id in the range
+    let refCovered = 0
+    let refCovers = true
+    for (let c = clock; c < clock + len; c++) {
+      if (ids.has(client, c)) refCovered++
+      else refCovers = false
+    }
+    t.assert(ids.covers(client, clock, len) === refCovers)
+    t.assert(ids.coveredLength(client, clock, len) === refCovered)
+    // cross-check against the allocating slice
+    const sliceCovered = ids.slice(client, clock, len).reduce((s, r) => r.exists ? s + r.len : s, 0)
+    t.assert(ids.coveredLength(client, clock, len) === sliceCovered)
+  }
+}
+
 /**
  * The struct that covers `clock` for the document's local client.
  *
diff --git a/tests/attribution.tests.js b/tests/attribution.tests.js
index 0645cb53..fc2964af 100644
--- a/tests/attribution.tests.js
+++ b/tests/attribution.tests.js
@@ -142,7 +142,7 @@ export const testChildListContent = () => {
 export const testAttributionSession1 = tc => {
   const { testConnector, users, text0, text1 } = init(tc, { users: 3 })
   users[0].gc = false
-  const globalAttributions = new Y.Attributions()
+  const globalAttributions = Y.createContentMap()
   const v1 = Y.cloneDoc(users[0])
   users.forEach(user => user.on('update', (update, _, ydoc, tr) => {
     if (!tr.local) return
@@ -154,20 +154,20 @@ export const testAttributionSession1 = tc => {
   text0.insert(0, 'a')
   text1.insert(0, 'b')
   testConnector.flushAllMessages()
-  const d1 = text0.toDelta({ renderer: Y.createDiffRenderer(v1, users[0], { attrs: globalAttributions }) })
+  const d1 = text0.toDelta({ renderer: Y.createDiffRenderer(v1, users[0], { attributions: globalAttributions }) })
   t.compare(d1, delta.create().insert('a', null, { insert: ['0'] }).insert('b', null, { insert: ['1'] }).done())
   const v2 = Y.cloneDoc(users[0])
   text0.delete(1, 1)
   text1.insert(2, 'c')
   testConnector.flushAllMessages()
-  const d2 = text0.toDelta({ renderer: Y.createDiffRenderer(v2, users[0], { attrs: globalAttributions }) })
+  const d2 = text0.toDelta({ renderer: Y.createDiffRenderer(v2, users[0], { attributions: globalAttributions }) })
   t.compare(d2, delta.create().insert('a').insert('b', null, { delete: ['0'] }).insert('c', null, { insert: ['1'] }).done())
 
-  const onlyUser0ChangesAttributed = {
-    inserts: Y.filterIdMap(globalAttributions.inserts, attrs => attrs.some(attr => attr.name === 'insert' && attr.val === '0')),
-    deletes: Y.filterIdMap(globalAttributions.deletes, attrs => attrs.some(attr => attr.name === 'delete' && attr.val === '0'))
-  }
-  const rendererUser0 = new Y.TwosetRenderer(onlyUser0ChangesAttributed.inserts, onlyUser0ChangesAttributed.deletes)
+  const onlyUser0ChangesAttributed = Y.createContentMap(
+    Y.filterIdMap(globalAttributions.inserts, attrs => attrs.some(attr => attr.name === 'insert' && attr.val === '0')),
+    Y.filterIdMap(globalAttributions.deletes, attrs => attrs.some(attr => attr.name === 'delete' && attr.val === '0'))
+  )
+  const rendererUser0 = new Y.AttributionsRenderer(onlyUser0ChangesAttributed)
   const d3 = text0.toDelta({ renderer: rendererUser0 })
   t.compare(d3, delta.create().insert('a', null, { insert: ['0'] }).insert('b', null, { delete: ['0'] }).insert('c').done())
   Y.undoContentIds(users[0], Y.createContentIdsFromContentMap(onlyUser0ChangesAttributed))
@@ -701,17 +701,17 @@ export const testRdtDeltaAttributionSanity = () => {
   const ydoc = new Y.Doc()
   const root = ydoc.get('root')
   const v1 = Y.cloneDoc(ydoc)
-  const attrs = new Y.Attributions()
+  const attributions = Y.createContentMap()
   ydoc.on('update', (update, _origin, doc, tr) => {
     if (!tr.local) return
     const uid = doc.clientID.toString()
     const cids = Y.createContentIdsFromUpdate(update)
-    Y.insertIntoIdMap(attrs.inserts, Y.createIdMapFromIdSet(cids.inserts, [Y.createContentAttribute('insert', uid)]))
-    Y.insertIntoIdMap(attrs.deletes, Y.createIdMapFromIdSet(cids.deletes, [Y.createContentAttribute('delete', uid)]))
+    Y.insertIntoIdMap(attributions.inserts, Y.createIdMapFromIdSet(cids.inserts, [Y.createContentAttribute('insert', uid)]))
+    Y.insertIntoIdMap(attributions.deletes, Y.createIdMapFromIdSet(cids.deletes, [Y.createContentAttribute('delete', uid)]))
   })
   root.insert(0, 'hello') // a suggestion relative to v1
   const uid = ydoc.clientID.toString()
-  root.useRenderer(Y.createDiffRenderer(v1, ydoc, { attrs }))
+  root.useRenderer(Y.createDiffRenderer(v1, ydoc, { attributions }))
   t.assert(root.delta.equals(delta.create().insert('hello', null, { insert: [uid] }).done()))
   t.assert(root.delta.equals(root.toDelta({ deep: true })))
 }
@@ -729,7 +729,7 @@ export const testRdtDeltaAttributionSanity = () => {
 export const testRdtFormatAcrossSuggestionDeletedDrift = () => {
   const doc = new Y.Doc({ gc: false })
   const suggestionDoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
-  const renderer = Y.createDiffRenderer(doc, suggestionDoc, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(doc, suggestionDoc, { attributions: Y.createContentMap() })
   doc.get('prosemirror').applyDelta(
     delta.create().insert([delta.create('paragraph', {}, 'hello world')]).done()
   )
@@ -767,7 +767,7 @@ const createSuggestionPair = (baseClientID, sdocClientID, useRootRenderer = true
   doc.clientID = baseClientID
   const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sdoc.clientID = sdocClientID
-  const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
   doc.get('prosemirror').applyDelta(
     delta.create().insert([delta.create('paragraph', {}, 'hello world')]).done()
   )
@@ -885,7 +885,7 @@ export const testRdtDeltaFreshRangeAfterItemMerge = () => {
   doc.clientID = 1
   const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sdoc.clientID = 2
-  const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
   doc.get('t').applyDelta(delta.create().insert('XY').done())
   const ytype = sdoc.get('t')
   ytype.useRenderer(renderer)
@@ -1009,7 +1009,7 @@ export const testRdtApplyDeltaNodeFormatOnTombstoneInverse = () => {
     doc.clientID = baseClientID
     const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
     sdoc.clientID = sdocClientID
-    const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+    const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
     doc.get('prosemirror').applyDelta(
       delta.create().insert([delta.create('paragraph', {}, 'aa'), delta.create('paragraph', {}, 'bb')]).done()
     )
@@ -1040,7 +1040,7 @@ export const testRdtApplyDeltaMixedFixCoordinates = () => {
     doc.clientID = baseClientID
     const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
     sdoc.clientID = sdocClientID
-    const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+    const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
     doc.get('prosemirror').applyDelta(
       delta.create().insert([
         delta.create('paragraph', {}, 'aa'), delta.create('paragraph', {}, 'hello world'), delta.create('paragraph', {}, 'cc')
@@ -1079,7 +1079,7 @@ export const testRdtApplyDeltaModifyAttrOnDeletedMapValue = () => {
     doc.clientID = baseClientID
     const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
     sdoc.clientID = sdocClientID
-    const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+    const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
     const title = doc.get('m').setAttr('title', new Y.Type())
     title.insert(0, 'hi')
     const m = sdoc.get('m')
@@ -1152,7 +1152,7 @@ export const testRdtApplyDeltaNestedTombstoneFixBubbles = () => {
     doc.clientID = baseClientID
     const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
     sdoc.clientID = sdocClientID
-    const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+    const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
     doc.get('prosemirror').applyDelta(
       delta.create().insert([delta.create('paragraph', {}, [delta.create('nested', {}, 'ww')])]).done()
     )
@@ -1186,7 +1186,7 @@ export const testRdtApplyDeltaPureDeleteOverTombstoneNoFix = () => {
     doc.clientID = baseClientID
     const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
     sdoc.clientID = sdocClientID
-    const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+    const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
     doc.get('prosemirror').applyDelta(
       delta.create().insert([
         delta.create('paragraph', {}, 'aa'), delta.create('paragraph', {}, 'hello world'), delta.create('paragraph', {}, 'cc')
@@ -1215,7 +1215,7 @@ export const testRdtApplyDeltaDeleteMidStruckChunkKeepsCursorSync = () => {
     doc.clientID = baseClientID
     const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
     sdoc.clientID = sdocClientID
-    const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+    const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
     doc.get('t').applyDelta(delta.create().insert('abc').done())
     doc.get('t').applyDelta(delta.create().retain(3).insert([delta.create('nA', {}, 'kk'), delta.create('nB', {}, 'qqq')]).done())
     const ytype = sdoc.get('t')
@@ -1250,7 +1250,7 @@ export const testRdtDeltaThroughDeletedAttrValue = () => {
     doc.clientID = baseClientID
     const sdoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
     sdoc.clientID = sdocClientID
-    const renderer = Y.createDiffRenderer(doc, sdoc, { attrs: new Y.Attributions() })
+    const renderer = Y.createDiffRenderer(doc, sdoc, { attributions: Y.createContentMap() })
     const title = doc.get('m').setAttr('title', new Y.Type())
     title.insert(0, 'hi')
     const m = sdoc.get('m')
@@ -1404,7 +1404,7 @@ export const testRdtDeletedSubtreeUndoScope = () => {
 export const testRdtAcceptingNodeInsertCacheDrift = () => {
   const doc = new Y.Doc({ gc: false })
   const suggestionDoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
-  const renderer = Y.createDiffRenderer(doc, suggestionDoc, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(doc, suggestionDoc, { attributions: Y.createContentMap() })
   renderer.suggestionMode = false
   doc.get('prosemirror').applyDelta(
     delta.create().insert([delta.create('paragraph', {}, 'base para')]).done()
@@ -1429,7 +1429,7 @@ export const testRdtAcceptingNodeInsertCacheDrift = () => {
   {
     const doc2 = new Y.Doc({ gc: false })
     const suggestionDoc2 = new Y.Doc({ isSuggestionDoc: true, gc: false })
-    const renderer2 = Y.createDiffRenderer(doc2, suggestionDoc2, { attrs: new Y.Attributions() })
+    const renderer2 = Y.createDiffRenderer(doc2, suggestionDoc2, { attributions: Y.createContentMap() })
     doc2.get('prosemirror').applyDelta(delta.create().insert([delta.create('paragraph', {}, 'base para')]).done())
     const ytype2 = suggestionDoc2.get('prosemirror')
     ytype2.useRenderer(renderer2)
@@ -1458,7 +1458,7 @@ export const testRdtAcceptingNodeInsertCacheDrift = () => {
 export const testRdtAcceptingNodeInsertRenderedAsSuggestion = () => {
   const doc = new Y.Doc({ gc: false })
   const suggestionDoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
-  const renderer = Y.createDiffRenderer(doc, suggestionDoc, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(doc, suggestionDoc, { attributions: Y.createContentMap() })
   renderer.suggestionMode = false
   doc.get('prosemirror').applyDelta(
     delta.create().insert([delta.create('paragraph', {}, 'base para')]).done()
@@ -1499,7 +1499,7 @@ export const testRdtAcceptingNodeInsertRenderedAsSuggestion = () => {
 export const testRdtPartialAcceptKeepsPendingChildSuggestions = () => {
   const doc = new Y.Doc({ gc: false })
   const suggestionDoc = new Y.Doc({ isSuggestionDoc: true, gc: false })
-  const renderer = Y.createDiffRenderer(doc, suggestionDoc, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(doc, suggestionDoc, { attributions: Y.createContentMap() })
   doc.get('prosemirror').applyDelta(delta.create().insert([delta.create('paragraph', {}, 'base para')]).done())
   const ytype = suggestionDoc.get('prosemirror')
   ytype.useRenderer(renderer)
@@ -1553,7 +1553,7 @@ export const testRdtBaseInsertIntoOverlappingFormatRangeCacheDrift = () => {
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -1599,7 +1599,7 @@ export const testRdtSuggestedInsertUnderTwoKeySuggestedFormatsCacheDrift = () =>
   base.clientID = 1
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 0
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -1646,7 +1646,7 @@ export const testRdtFormattedBaseInsertUnderTwoKeySuggestedFormatsCacheDrift = (
   base.clientID = 1
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 0
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -1698,7 +1698,7 @@ export const testRdtBaseFormatEndingInsideSuggestedFormatRangeFormatValueCacheDr
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -1748,7 +1748,7 @@ export const testRdtSuggestedRemovalOfOverriddenBaseFormatCacheDrift = () => {
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -1797,7 +1797,7 @@ export const testRdtStagedSuggestedUnformatOfBaseFormatCacheDrift = () => {
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -1850,7 +1850,7 @@ export const testRdtAcceptAllOfSameValueSuggestedFormatCacheDrift = () => {
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -1901,7 +1901,7 @@ export const testRdtRejectAllOverlappingSameKeyFormatProvenanceResidual = () =>
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -1963,7 +1963,7 @@ export const testRdtSplitFormatMarkerPairPartialAcceptThenUnformatCacheDrift = (
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -2025,7 +2025,7 @@ export const testRdtPartialAcceptSkippingUnformatOpenMarkerCacheDrift = () => {
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -2093,7 +2093,7 @@ export const testRdtBaseUnformatInsideBlockDeletedParagraphCacheDrift = () => {
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
@@ -2149,7 +2149,7 @@ export const testRdtBaseFormatClearInsideSuggestionDeletedParagraphCacheDrift =
   base.clientID = 0
   const sugg = new Y.Doc({ isSuggestionDoc: true, gc: false })
   sugg.clientID = 1
-  const renderer = Y.createDiffRenderer(base, sugg, { attrs: new Y.Attributions() })
+  const renderer = Y.createDiffRenderer(base, sugg, { attributions: Y.createContentMap() })
   renderer.suggestionMode = true
   const bt = base.get('t')
   const st = sugg.get('t')
diff --git a/tests/y-array.tests.js b/tests/y-array.tests.js
index 4b044387..8a5049ef 100644
--- a/tests/y-array.tests.js
+++ b/tests/y-array.tests.js
@@ -467,11 +467,11 @@ export const testAttributedContent = _tc => {
    */
   const yarray = ydoc.get()
   yarray.insert(0, [1, 2])
-  let renderer = /** @type {AbstractRenderer?} */ (Y.baseRenderer)
+  let renderer = /** @type {AbstractRenderer?} */ (null)
 
   ydoc.on('afterTransaction', tr => {
-    // renderer = new TwosetRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
-    renderer = new Y.TwosetRenderer(Y.createIdMapFromIdSet(tr.insertSet, []), Y.createIdMapFromIdSet(tr.deleteSet, []))
+    // renderer = new AttributionsRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
+    renderer = new Y.AttributionsRenderer(Y.createContentMap(Y.createIdMapFromIdSet(tr.insertSet, []), Y.createIdMapFromIdSet(tr.deleteSet, [])))
   })
   t.group('insert / delete', () => {
     ydoc.transact(() => {
diff --git a/tests/y-map.tests.js b/tests/y-map.tests.js
index d084d45e..7fb03299 100644
--- a/tests/y-map.tests.js
+++ b/tests/y-map.tests.js
@@ -1,6 +1,6 @@
 import * as Y from '../src/index.js'
 import { init, compare, applyRandomTests, Doc } from './testHelper.js' // eslint-disable-line
-import { baseRenderer, TwosetRenderer } from '../src/utils/Renderer.js'
+import { AttributionsRenderer } from '../src/utils/Renderer.js'
 import { createIdMapFromIdSet } from '../src/utils/ids.js'
 import * as t from 'lib0/testing'
 import * as prng from 'lib0/prng'
@@ -552,11 +552,11 @@ export const testYmapEventHasCorrectValueWhenSettingAPrimitiveFromOtherUser = tc
 export const testAttributedContent = _tc => {
   const ydoc = new Y.Doc({ gc: false })
   const ymap = ydoc.get()
-  let renderer = /** @type {AbstractRenderer?} */ (baseRenderer)
+  let renderer = /** @type {AbstractRenderer?} */ (null)
 
   ydoc.on('afterTransaction', tr => {
-    // renderer = new TwosetRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
-    renderer = new TwosetRenderer(createIdMapFromIdSet(tr.insertSet, []), createIdMapFromIdSet(tr.deleteSet, []))
+    // renderer = new AttributionsRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
+    renderer = new AttributionsRenderer(Y.createContentMap(createIdMapFromIdSet(tr.insertSet, []), createIdMapFromIdSet(tr.deleteSet, [])))
   })
   t.group('initial value', () => {
     ymap.setAttr('test', 42)
diff --git a/tests/y-text.tests.js b/tests/y-text.tests.js
index 88b9e7f8..4f330a27 100644
--- a/tests/y-text.tests.js
+++ b/tests/y-text.tests.js
@@ -4,7 +4,7 @@ import * as prng from 'lib0/prng'
 import * as math from 'lib0/math'
 import * as delta from 'lib0/delta'
 import { createIdMapFromIdSet } from '../src/utils/ids.js'
-import { baseRenderer, TwosetRenderer, createSnapshotRenderer } from '../src/utils/Renderer.js'
+import { AttributionsRenderer, createSnapshotRenderer } from '../src/utils/Renderer.js'
 
 const { init, compare } = Y
 
@@ -1900,11 +1900,11 @@ export const testAttributedContent = _tc => {
   const ydoc = new Y.Doc({ gc: false })
   const ytext = ydoc.get()
   ytext.insert(0, 'Hello World!')
-  let renderer = /** @type {AbstractRenderer?} */ (baseRenderer)
+  let renderer = /** @type {AbstractRenderer?} */ (null)
 
   ydoc.on('afterTransaction', tr => {
-    // renderer = new TwosetRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
-    renderer = new TwosetRenderer(createIdMapFromIdSet(tr.insertSet, []), createIdMapFromIdSet(tr.deleteSet, []))
+    // renderer = new AttributionsRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
+    renderer = new AttributionsRenderer(Y.createContentMap(createIdMapFromIdSet(tr.insertSet, []), createIdMapFromIdSet(tr.deleteSet, [])))
   })
   t.group('insert / delete / format', () => {
     ytext.applyDelta(delta.create().retain(4, { italic: true }).retain(2).delete(5).insert('attributions').done())
@@ -1944,8 +1944,8 @@ export const testAttributedDiffing = _tc => {
   const attributedInsertions = createIdMapFromIdSet(insertionSetDiff, [Y.createContentAttribute('insert', 'Bob')])
   const attributedDeletions = createIdMapFromIdSet(deleteSetDiff, [Y.createContentAttribute('delete', 'Bob')])
   // now we can define an attribution manager that maps these changes to output. One of the
-  // implementations is the TwosetRenderer
-  const renderer = new TwosetRenderer(attributedInsertions, attributedDeletions)
+  // implementations is the AttributionsRenderer
+  const renderer = new AttributionsRenderer(Y.createContentMap(attributedInsertions, attributedDeletions))
   // we render the attributed content with the renderer
   const attributedContent = ytext.toDelta({ renderer })
   console.log(JSON.stringify(attributedContent.toJSON(), null, 2))
@@ -1954,6 +1954,52 @@ export const testAttributedDiffing = _tc => {
   console.log(Y.encodeIdMap(attributedInsertions).length)
 }
 
+/**
+ * The `renderedContent` option decouples "what is visible" from the doc's deleted state and from
+ * attributions: content in `renderedContent` renders normally (even if deleted → "restore"), alive
+ * content omitted from it is hidden, and attributions always render (even outside it).
+ *
+ * @param {t.TestCase} _tc
+ */
+export const testAttributionsRendererRenderedContent = _tc => {
+  const ydoc = new Y.Doc({ gc: false }) // restore requires gc:false (no rehydration of gc'd content)
+  ydoc.clientID = 1
+  const ytext = ydoc.get()
+  ytext.insert(0, 'Hello World!')
+  ytext.delete(5, 6) // delete ' World' (clock 5..10) → the visible doc is 'Hello!'
+  t.compare(ytext.toDelta().toJSON(), delta.create().insert('Hello!').done().toJSON()) // sanity: default hides the deletion
+
+  const emptyAttributions = Y.createContentMap()
+  const aliveSet = Y.createInsertSetFromStructStore(ydoc.store, true) // {0..4, 11}
+
+  t.group('restore: deleted content in renderedContent renders normally', () => {
+    const renderedContent = Y.createInsertSetFromStructStore(ydoc.store, false) // all content incl. deleted
+    const renderer = new AttributionsRenderer(emptyAttributions, { renderedContent })
+    const expected = delta.create().insert('Hello World!')
+    const rendered = ytext.toDelta({ renderer })
+    t.assert(rendered.equals(expected))
+  })
+
+  t.group('hide: alive content omitted from renderedContent renders as nothing', () => {
+    const hidden = Y.createIdSet()
+    hidden.add(1, 1, 4) // hide 'ello' (clock 1..4)
+    const renderer = new AttributionsRenderer(emptyAttributions, { renderedContent: Y.diffIdSet(aliveSet, hidden) })
+    const expected = delta.create().insert('H!')
+    const rendered = ytext.toDelta({ renderer })
+    t.assert(rendered.equals(expected))
+  })
+
+  t.group('attributions always render, even outside renderedContent', () => {
+    const deletedRange = Y.createIdSet()
+    deletedRange.add(1, 5, 6) // ' World'
+    const attributions = Y.createContentMap(Y.createIdMap(), createIdMapFromIdSet(deletedRange, [Y.createContentAttribute('delete', 'bob')]))
+    const renderer = new AttributionsRenderer(attributions, { renderedContent: aliveSet })
+    const expected = delta.create().insert('Hello').insert(' World', {}, { delete: ['bob'] }).insert('!')
+    const rendered = ytext.toDelta({ renderer })
+    t.assert(rendered.equals(expected))
+  })
+}
+
 // RANDOM TESTS
 
 let charCounter = 0
@@ -2219,6 +2265,54 @@ export const testRendererDefaultPerformance = tc => {
   })
 }
 
+/**
+ * Benchmark the generic fast path (default / no renderer) against an {@link AttributionsRenderer}
+ * configured with *no* attributions (an empty {@link ContentMap}) and a custom `renderedContent`
+ * set to the doc's full insert set. Since the insert set also contains the ids of deleted content,
+ * the renderer *restores* every deletion — rendering the whole document normally, without
+ * attributions — while alive content (fully covered by `renderedContent`) still takes the generic
+ * fast path. This measures the renderer's restore path (`hasItem`'s restore branch, `readContent`'s
+ * custom-`renderedContent` path, and `contentLength` via `coveredLength`) against the default.
+ *
+ * @param {t.TestCase} tc
+ */
+export const testRendererAttributionsPerformance = tc => {
+  const N = 10000
+  const MaxDeletionLength = 5 // 25% chance of deletion
+  const MaxInsertionLength = 5
+  const ydoc = new Y.Doc({ gc: false }) // keep deleted content so the delete set renders real content
+  const ytext = ydoc.get()
+  for (let i = 0; i < N; i++) {
+    if (prng.bool(tc.prng) && prng.bool(tc.prng) && ytext.length > 0) {
+      const index = prng.int31(tc.prng, 0, ytext.length - 1)
+      const len = prng.int31(tc.prng, 0, math.min(ytext.length - index, MaxDeletionLength))
+      ytext.delete(index, len)
+    } else {
+      const index = prng.int31(tc.prng, 0, ytext.length)
+      const content = prng.utf16String(tc.prng, MaxInsertionLength)
+      ytext.insert(index, content)
+    }
+  }
+  // no attributions; renderedContent = the full insert set, which also covers deleted ids, so every
+  // deletion is restored and rendered normally
+  const insertSet = Y.createInsertSetFromStructStore(ydoc.store, false)
+  // const deleteSet = Y.createDeleteSetFromStructStore(ydoc.store)
+  const renderer = new AttributionsRenderer(Y.createContentMap(), { renderedContent: insertSet })
+  t.info(`number of changes: ${N / 1000}k`)
+  t.info(`length of visible text: ${ytext.length}`)
+  const M = 10
+  t.measureTime(`default renderer (fast path): toDelta() <executed ${M} times>`, () => {
+    for (let i = 0; i < M; i++) {
+      ytext.toDelta()
+    }
+  })
+  t.measureTime(`AttributionsRenderer (no attributions, renderedContent = insert set): toDelta({ renderer }) <executed ${M} times>`, () => {
+    for (let i = 0; i < M; i++) {
+      ytext.toDelta({ renderer })
+    }
+  })
+}
+
 /**
  * @param {t.TestCase} tc
  */
diff --git a/tests/y-xml.tests.js b/tests/y-xml.tests.js
index 2bd3efc2..37a8f088 100644
--- a/tests/y-xml.tests.js
+++ b/tests/y-xml.tests.js
@@ -139,10 +139,10 @@ export const testFragmentAttributedContent = _tc => {
   const elem3 = Y.Type.from(delta.create().insert('world'))
   yfragment.insert(0, [elem1, elem2])
   ydoc.get().insert(0, [yfragment])
-  let renderer = /** @type {AbstractRenderer?} */ (Y.baseRenderer)
+  let renderer = /** @type {AbstractRenderer?} */ (null)
   ydoc.on('afterTransaction', tr => {
-    // renderer = new TwosetRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
-    renderer = new Y.TwosetRenderer(Y.createIdMapFromIdSet(tr.insertSet, []), Y.createIdMapFromIdSet(tr.deleteSet, []))
+    // renderer = new AttributionsRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
+    renderer = new Y.AttributionsRenderer(Y.createContentMap(Y.createIdMapFromIdSet(tr.insertSet, []), Y.createIdMapFromIdSet(tr.deleteSet, [])))
   })
   t.group('insert / delete', () => {
     ydoc.transact(() => {
@@ -167,10 +167,10 @@ export const testElementAttributedContent = _tc => {
   const elem2 = delta.create('span').done()
   const elem3 = delta.create().insert('world').done()
   yelement.insert(0, [elem1, elem2])
-  let renderer = /** @type {AbstractRenderer?} */ (Y.baseRenderer)
+  let renderer = /** @type {AbstractRenderer?} */ (null)
   ydoc.on('afterTransaction', tr => {
-    // renderer = new TwosetRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
-    renderer = new Y.TwosetRenderer(Y.createIdMapFromIdSet(tr.insertSet, []), Y.createIdMapFromIdSet(tr.deleteSet, []))
+    // renderer = new AttributionsRenderer(createIdMapFromIdSet(tr.insertSet, [new Y.Attribution('insertAt', 42), new Y.Attribution('insert', 'kevin')]), createIdMapFromIdSet(tr.deleteSet, [new Y.Attribution('delete', 'kevin')]))
+    renderer = new Y.AttributionsRenderer(Y.createContentMap(Y.createIdMapFromIdSet(tr.insertSet, []), Y.createIdMapFromIdSet(tr.deleteSet, [])))
   })
   t.group('insert / delete', () => {
     ydoc.transact(() => {