Add release note for comment thread collapsible state

release-notes/v1_95.md

@@ -341,6 +341,10 @@ The use of language model tools is complex, and this API does not hide that comp
 
 The [VS Code Speech](https://marketplace.visualstudio.com/items?itemName=ms-vscode.vscode-speech) extension is updated to the August version of the [Azure Speech SDK](https://learn.microsoft.com/en-us/azure/ai-services/speech-service/releasenotes?tabs=speech-sdk#speech-sdk-140-2024-august-release) and comes with newer models for speech-to-text recognition. You should see improved results with this update for the [speech-to-text integrations in VS Code](https://code.visualstudio.com/docs/editor/voice), such as Copilot Chat.
 
+### Comment Thread `collapsibleState`
+
+The expand/collapse state of a `CommentThread` can be changed using the new `CommentThread.collapsibleState` property, even once the thread has already been shown. Previously, this property would only be respected the first time the comment thread was shown.
+
 ## Preview Features
 
 ### TypeScript 5.7