Still a WIP, but here's the deets so far:
## No more throwing canceled tokens
Throwing exceptions is expensive and since we essentially cancel tokens
anytime someone is typing beyond the debounce, we could be throwing
exceptions a ton during search. Since we don't care about those past
executions, now they just `return`.
## Reduced number of apps returned in search
While users can specify how many apps (no limit, 1, 5), if they specify
no limit, we hard limit it at 10. For a few reasons, fuzzy search gets
_really_ fuzzy sometimes and gives answers that users would think is
just plain wrong and they make the response list longer than it needs to
be.
## Fuzzy search: still fuzzy, but faster
Replaced `StringMatcher` class with `FuzzyStringMatcher`.
`FuzzyStringMatcher` is a C# port by @zadjii-msft of the Rust port by
@lhecker for [microsoft/edit](https://github.com/microsoft/edit), which
I believe originally came from [VS
Code](https://github.com/microsoft/vscode). It's a whole fuzzy rabbit
hole. But it's faster than the `StringMatcher` class it replaced.
## Fallbacks, you need to fall back
"In the beginning, fallbacks were created. This had made many people
very angry and has been widely regarded as a bad move."
Hitchhiker's Guide to the Galaxy jokes aside, fallbacks are one cause of
slower search results. A few modifications have been made to get them
out of the way without reverting their ability to do things dynamically.
1. Fallbacks are no longer scored and will always* appear at the bottom
of the search results
2. In updating their search text, we now use a cancellation token to
stop processing previous searches when a new keypress is recorded.
## * But Calculator & Run are special
So, remember when I said that all fallbacks will not be ranked and
always display at the bottom of the results? Surprise, some will be
ranked and displayed based on that score. Specifically, Calculator and
Run are fallbacks that are whitelisted from the restrictions mentioned
above. They will continue to act as they do today.
We do have the ability to add future fallbacks to that whitelist as
well.
---
## Current preview
Updated: 2025-09-24
https://github.com/user-attachments/assets/c74c9a8e-e438-4101-840b-1408d2acaefd
---
Closes#39763Closes#39239Closes#39948Closes#38594Closes#40330
