546816 - [Linux/Gnome] Improve Gnome theme detection for Firefox.next

Status: RESOLVED WONTFIX

(Core :: CSS Parsing and Computation, defect)

Description

[Alex Faaborg [:faaborg] (Firefox UX)]

This is the Linux equivalent to bug 543910, which covers the same issue on windows.  For the next Firefox theme we are going to need to have CSS selectors for all of the common Gnome themes.  These will be used in a few cases where we have to provide different images in the UI for each theme.

In the event that the OS theme is not one of the common ones we are aware of, we will be falling back to generic images that can work with any potential theme (similar to how we have images designed to appear over any persona).

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

See bug 543910 comment 6 (and likely some earlier and later comments in the bug) for comments on what code likely needs to change for this.

I'm not sure whether we'll be able to detect the name of the theme on Linux or whether we can determine certain known themes based on parameters.  I suspect it's likely we'll be able to pull theme names out of something, though.


The other interesting issue here is that there are different aspects to the theme that are easily configurable separately:  on Ubuntu there's relatively prominent UI (the "Customize..." button) for changing the controls, colors, window border, icons, and mouse cursors separately.

So we may want separate selectors for the different theme aspects.  Having separate selectors also reduces the number of themes, since many of the themes in the primary list are different mixes of a smaller set.

For the record, I actually configure these themes separately.  I do this because the icon set in the default Ubuntu theme is rather incomplete (e.g., no icon for the default IM client when running in the system tray).  This means I have a bunch of prominent icons that would be really jarring if I used the default icon theme.

Comment 2

[Michael Ventnor]

Using the theme name would be completely unsustainable. Themes change (Ubuntu just got rid of their orange!) and there are too many themes for us to have a case for each of them.

A far better method would be to expose whatever the theme wants. We're already pretty good with CSS colours. Maybe if we used more SVG or Canvas in the UI, we'd be able to use native colours without having to use this hacky images approach.

Comment 3

[Dão Gottwald [:dao]]

wontfix'ing as per comment 2