Moving in and out of element boundaries in Firefox

[Jakub Ś]

This is the continuation or extension of #7796.

1. Open replacebycode sample in Firefox
2. Select sample text with a mouse
3. Apply inline "Variable" style or "Cosmic Sans MS" font style
4. Click behind the dot
5. Path shows that you are no longer inside span tag.
6. Press ENTER and start typing - inline style is not applied.
7. Put cursor behind the dot, press LEFT_ARROW, press RIGHT_ARROW
8. You should be behind the dot but this time in side VAR od SPAN tag.
9. Press ENTER and start typing - styles are applied.
10. It all depends whether Firefox decides whether you have left element boundaries or not.

After discussoin with @wwalc we have decided to create such ticket and link it to #7796 just to mark that this is not only about pasting.