bug#56637: 28.1.90; [FR] Allow a way around font-lock-mode being unconditionally disabled in " *hidden*" buffers

[Lars Ingebrigtsen]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> Sorry, it is a typo. I did mean "the fontification *is* using
>> (font-lock-ensure)".
>
> Ah, good, thanks.
>
>> We do use `font-lock-ensure', but it does not always produce the same
>> results with/without font-lock-mode enabled.
>
> I'm not completely surprised, because I remember when writing
> `font-lock-ensure` that there are many corner cases some of which seem
> very difficult to fix without actually enabling `font-lock-mode`, but we
> should still strive to be "as close as possible", so ... do you have
> a bug report with some concrete cases we could try to fix?

Would it make sense to make `font-lock-ensure' try harder here, and
(temporarily) force font-lock mode on (even in temporary buffers) if it
isn't already?

I saw that other proposed patch (with `font-lock-mode-unconditionally'),
but I'm not sure that would be as obvious a solution.