Code distorting while highlighting text

[garitudorsmith]

I've been working in WakkaIII today and sometimes when I highlight something, other parts of the text and TEI markup duplicate and replace other text and markup. Sometimes if I click on it a bunch of times it goes back to normal.

See here on line 3 where the < / line > should be:

It seems to be only a display issue - you can see that it went away when I clicked saved and the transcription is normal in the preview:
https://github.com/CoEDL/nyingarn-workspace/assets/152601883/f87fe268-9074-4ae0-8826-43d5200dd7cc