feat(api/ui): api support for showing / hiding the native tab bar

[integeresting]

closes #18

Basically just did the things written in the issue.
Chose hide over true since I found some interesting options like autohide when I looked through the CSS hacks.

Included the CSS in a separate file, since it is pretty long. I kept the source references which should make it MPL 2.0 compliant.

Quick demo:

glide-tabs-demo.mp4

Also included a small description and some sanity tests.

I also have a similar setup for the nav bar / main toolbar, which I did not include but I find very handy (I use librewolf without any bars).

Demo for that:

glide-navbar-demo.mp4

[RobertCraigie]

This is so cool!!!!!! Thank you for working on this :)

[RobertCraigie]

I think it'd be slightly better to instead include the .css files directly in the browser build, as updating any of them is as simple as a cp or a curl -o from the firefox-csshacks repository.

That does complicate the internal setters somewhat though as I'm not aware of a synchronous equivalent to ChromeUtils.importESModule() for .css / arbitrary text files.

So if we can't find a builtin way to do that, we'd need to add that internal API somehow, or make the set native_tabs() function asynchronous and use the fetch_resource() helper, which maybe is fine? I'm not sure, it definitely feels weird.

Any thoughts?

[integeresting]

Updating them might not be that simple, since some have multiple use cases and require tweaks depending on what you want to achieve (see autohide for vertical tabs). So there might be a patching step there.

It would ofc be nicer to have the CSS in proper files. Could they be linked to with style tags when bundled in?

From the user perspective I would also feel weird if the "hide some toolbar" option had a micro package manager integrated. 😄

[integeresting]

Great feedback, tysm! :)

[RobertCraigie]

Looks great, thank you! Some minor comments

[RobertCraigie]

Wait actually it looks like autohide doesn't work for me on macOS, it's just always hidden...

Screen.Recording.2025-12-20.at.8.24.02.pm.mov

I suspect this is a bug with firefox-csshacks though so... I think we can just document that autiohide doesn't work on macOS for now

[integeresting]

Shame, can't have nice things. I'll include a warning.

[RobertCraigie]

I had a last minute realisation that this should really be glide.o.native_tabs as it just makes sense to put it there as it is an "option"; it also means it could just work in other cases, e.g. glide.bo.native_tabs which is nice.

I pushed an extra commit making that change so you don't have to deal with the thrash :)

Unfortunately glide.bo.native_tabs = "hide"; doesn't quite work right now as glide.bo doesn't call our custom setter, but thats a more general issue we can fix in a follow-on.

Thanks again!

[integeresting]

Sounds good! Really appreciate the help
Thank you