GitHub Copilot Chat prompt editor keeps ghost highlights of file references.

[garretwilson]

1. Edit a prompt (in my case an already-submitted prompt) and add a file reference such as #file:foobar.txt.
2. After a while, delete the entire prompt and start over.

Expected: The prompt will be edited normally, as if no file references had ever been added.
Actual: Certain parts of the text will be shown highlighted, as if ghosts of the previous file references.

This is directly related to #281766 and indirectly related to #280071.

Version: 1.107.0 (user setup)
Commit: 618725e67565b290ba4da6fe2d29f8fa1d4e3622
Date: 2025-12-10T07:43:47.883Z
Electron: 39.2.3
ElectronBuildId: 12895514
Chromium: 142.0.7444.175
Node.js: 22.21.1
V8: 14.2.231.21-electron.0
OS: Windows_NT x64 10.0.26200

[garretwilson]

There are many variations; see in particular my other comment on #281766.