The corresponding font is not highlighted for lists when clicking the "Font size" button

[Softvision-CristinaBadescu]

[Notes]:

• Since the lists have the "Aa" button displayed, I assume that the corresponding font size should be highlighted, or another option, such as "Choose heading" should be displayed.

[Affected versions]:

• Firefox 58.0.1 and up

[Affected Platforms]:

• All Windows
• All Mac
• All Linux

[Prerequisites]:

• Have a Firefox profile with the latest "Firefox Notes" add-on version (2.2.0dev custom build from 2018-02-01) installed.
• Have some text organized in a list (ordered or numbered).

[Steps to reproduce]:

1. Open Firefox browser with the profile from prerequisites.
2. Click the text from the list.
3. Click the font size button and observe the highlighted font size.

[Expected result]:

• The "Body text" is highlighted.
  or
• Another option such as "Choose heading" is highlighted.

[Actual result]:

• None of the displayed font size is highlighted.

[Additional Notes]:

• This issue is not reproducible with other text editors such as Google Docs or LibreOffice documents.
• Here is a screen recording with this issue:
  

[Natim]

This is because when in list mode we are not in text mode, we can't mix lists and titles either.

[vladikoff]

Need to file a ckeditor bug ...