On 16/05/2020 19.03, Juri Linkov wrote:
>>>>> I think the problem is that tab-line is declared a basic face, but its
>>>>> defface form is not in faces.el.
>>>>
>>>> Ah, good catch.  Current there's a defface for tab-bar in lisp/tab-bar, and since that's preloaded it works, but the defface for tab-line is in lisp/tab-line.el and so isn't preloaded.
>>>> Should I move both to faces.el?
>>>>
>>> Yes, I think so.
>>
>> Thanks.  I will ask Juri to confirm before moving them, because I realize now that they have a custom group.
>> Juri (CC'd; hi Juri!), was there a reason to make tab-bar and tab-line basic faces?  I see they are both in their own files and groups, instead of being in faces.el.
> 
> Actually, no reason other than consistency of faces belonging to the
> same file where they are used.  But if it will fix the technical problem,
> please move them to faces.el, especially given the fact that their
> counterpart tool-bar face is already defined in faces.el.

Thanks a lot.  The attached patch does that.