Investigate why CM event timing fix didn't fix #2806

[njx]

#2806 was fundamentally due to an event timing issue, where CM wasn't sending out the redraw event for inline editors at the right time (it was sending it before the widget was actually fully re-added to the DOM). That issue was addressed upstream in codemirror/codemirror5@1c8a36e, but that CM fix didn't seem to actually fix our problem. We should try to figure out why, and more generally test whether there are other ramifications of the event timing changes in that commit.

[njx]

Reviewed.

[njx]

This bug is pretty old and it's not clear that doing this investigation at this point would be helpful. Closing.