Edge Stable 103.0.1264.37 breaks group policy management of the browser - Critical

This issue is caused by a race condition.

Group Policy update works by
1) Deleting the old policies from the registry
2) Writing the current policies to the registry
3) Chromium reloading new policy data out of the registry

In v103, a regression was introduced by new registry-monitoring code. This code would detect that the keys had changed at [point 1] and the browser's in-process policy would be refreshed before the current policy data had been fully written to the registry by the GP Update. As a consequence, the browser process could end up with a "partial" (or empty) set of policies applied. 

The problem's reproducibility will vary depending upon how short the time gap is between old policies being deleted from the registry and new policies being written. The visibility of the problem also varies-- only policies that support Dynamic Refresh are impacted, and many policies do not have side-effects that are immediately user-visible.

The fix is to stop monitoring the registry keys directly.