`dark-mark-view-*` Makes it hard to use `render()`

[nadjitan]

Describe the bug
The background/highlight color does not match with the font size. I think it's because of the span elements that has dark-mark-view-* attributes.

To Reproduce

1. Add texts
2. Make some parts of the text bigger
3. Add background color
   Sample stackblitz

Misc

• Node version:
• Package manager: NPM
• Browser: Zen Browser