diff --git a/packages/core/api/sync/collector.js b/packages/core/api/sync/collector.js
index 6884e7298..cd3f29c67 100644
--- a/packages/core/api/sync/collector.js
+++ b/packages/core/api/sync/collector.js
@@ -47,7 +47,7 @@ class Collector {
    * @param {Array} array
    * @returns {Array}
    */
-  _collect(type, array, isForceSync) {
+  _collect(collectionId, array, isForceSync) {
     if (!array.length) return [];
 
     const result = array.reduce((prev, item) => {
@@ -60,18 +60,18 @@ class Collector {
       if (item.localOnly) {
         prev.push({
           id: item.id,
-          type,
+          collectionId,
           deleted: true,
           dateModified: Date.now(),
         });
       } else if (isUnsynced && isSyncable) {
-        prev.push({ ...item, type });
+        prev.push({ ...item, collectionId });
       }
 
       return prev;
     }, []);
     this.logger.info(
-      `Collected items: ${type} (${result.length}/${array.length})`
+      `Collected items: ${collectionId} (${result.length}/${array.length})`
     );
     return result;
   }
diff --git a/packages/core/api/sync/index.js b/packages/core/api/sync/index.js
index eeb60e6d7..166d41f52 100644
--- a/packages/core/api/sync/index.js
+++ b/packages/core/api/sync/index.js
@@ -257,7 +257,9 @@ class Sync {
 
     const arrays = data.items.reduce(
       (arrays, item) => {
-        arrays.types.push(item.type);
+        arrays.types.push(item.collectionId);
+
+        delete item.collectionId;
         arrays.items.push(item);
         return arrays;
       },
diff --git a/packages/core/api/sync/merger.js b/packages/core/api/sync/merger.js
index 6cea762b8..08b911946 100644
--- a/packages/core/api/sync/merger.js
+++ b/packages/core/api/sync/merger.js
@@ -107,7 +107,11 @@ class Merger {
     if (deserialized.alg && deserialized.cipher) return deserialized;
 
     let type = deserialized.type;
-    if (!type && deserialized.data) type = "tiptap";
+    // temporary fix for streetwriters/notesnook#751
+    if (type === "content") {
+      type = "tiptap";
+      deserialized.type = type;
+    }
 
     if (!migrations[version]) {
       throw new Error(
@@ -119,7 +123,6 @@ class Merger {
 
     const migrate = migrations[version][type];
     if (migrate) {
-      console.log(migrate, version, type);
       return migrate(deserialized);
     }
     return deserialized;
diff --git a/packages/core/content-types/index.js b/packages/core/content-types/index.js
index 2f6f4f1e4..93f263fb3 100644
--- a/packages/core/content-types/index.js
+++ b/packages/core/content-types/index.js
@@ -5,6 +5,8 @@ export function getContentFromData(type, data) {
     case "tiptap":
       return new Tiptap(data);
     default:
-      return null;
+      throw new Error(
+        `Unknown content type: "${type}". Please report this error at support@streetwriters.co.`
+      );
   }
 }