Tested with Dev Spaces 3.3.0:

• devspaces-operator-bundle:3.3-175
• Index Image: brew.registry.redhat.io/rh-osbs/iib:358179'
• OCP 4.10

Test scenario:
1. Create and run empty workspace
2. Open workspace page
3. Go to extensions view
There are all 32 built-in extensions appear in "devspaces.apps.ocp410-next-ds.crw-qe.com - Installed" section.

5. Reload Visual Studio Code
6. Wait workspace is reloaded

There is no build-in extensions in "devspaces.apps.ocp410-next-ds.crw-qe.com - Installed" section