Thanks for the report. I verified the context menu defect on Windows and Mac Mohave.  The menu and shortcuts still work on both.

This regression was introduced by the first PR for #39885.  I mistakenly delayed the fixer, PR-18951, to finish new tests. (On current Win10, disabled items are nearly black dark gray that I easily confuse with enabled black.  On Mac, the contrast between its light-medium gray and black is unmistakable.)

I polished the fixer and merged it, with only manual testing, to immediately fix the regression.  I re-labelled this issue to add an automated test that would have caught it.