Steps to reproduce

1. Turn highlighting on
2. Open some page in WikiEditor
3. Move the cursor somewhere and start typing

Expected behavior
Cursor should stay where it is when MediaWiki-extensions-CodeMirror (after a delay) loads

Current behavior
In the middle of typing, when MediaWiki-extensions-CodeMirror loads finally, the cursor moves at the beginning and the half of the word is at the former place and half is at the beginning

Comment
I understand a delay between WikiEditor and MediaWiki-extensions-CodeMirror, I don't mind this delay (highlighting is not a thing, which should be immediately available, thus this delay is 100 % ok in my opinion), but after this delay the cursor just should stay at its position and not jump at the beginning