Does "align on alignment marker" work in Mathematica 12.3

In Mathematica 12.1 (and previous versions), you can insert a cell of style DisplayFormula into a notebook, using Format/Style/DisplayFormula from the menu. You can then use Format/Text Alignment/On AlignmentMarker to set it to align lines of the DisplayFormula on alignment marks, which can be inserted by typing <esc>am<esc>. Other than that, such a cell acted like a left-aligned Displayformula cell. (There was, as far as I can find, no way to simultaneously set align on marker and left/right/center alignment.)

I just upgraded to 12.3, and this no longer works. If I insert a DisplayFormula and set it to align on markers, text in the cell disappears from the display. It has not been deleted--anything you type becomes visible again if you change the alignment to something else. In fact, if you type a lot into a marker-aligned DisplayFormula, for instance, by holding down the x key and letting autorepeat do its work, you can see that the contents of the cell seem to be centered somewhere off-window to the right. This is a purely cosmetic problem, but still very annoying.

Question: Has anyone else encountered this problem? Or figured out a way to solve it?

Thanks for any help.

• As far as I know was Format/Text Alignment/On AlignmentMarker broken in 12.2 (Frontend crash). So something might have been fixed in 12.3 but probably not 100% correct. I would report the issue to WRI. May 22, 2021 at 16:15