4e32b01 was a bad change that makes it more likely that Copilot chat and completions extension are installed and activated before the user is signed in and signed up for Copilot. This has 2 consequences:

Copilot completions shows warnings and is not function initially, but recovers eventually:

Copilot Chat shows a "Sign in" button in its view, that is a no-op when you click it. You have to restart VS Code or reload the window to get out of this.

Suggested fix is to revert 4e32b01 in #254961