Meaning of clock icon in VS Code source control

• The clock icon is the progress marker, or 'VSCode is still working on this...' marker.
• The designer's expectation is that this would be a momentary notification, not a long one.
• When you open a new directory for the first time, but do not have a .gitignore set up, this means it wants to slurp your node_modules or directory of intermediate object files and such. This takes a long time, or forever if it crashes and restarts, and so you keep seeing the icon.
• Add a .gitignore file.
• Restart VS Code if necessary. If you still have trouble, consider sacrificing a live chicken over the CPU (reports say a Rhode Island Red works, but YMMV).

The clock is the "Progress Badge" which is visible while VS Code is getting repository info and status:

You can disable it in settings:

{ 
  // controls whether git actions should show progress
  "git.showProgress": true
}