Although ANGLE does generate an INVALID_OPERATION error for UseProgram if the current transform feedback object is active and not paused, WebKit proceeds with switching the program anyway.
Committed 252432@main (f1fd6ea39943): <https://commits.webkit.org/252432@main> Reviewed commits have been landed. Closing PR #2335 and removing active labels.
<rdar://problem/96985224>