User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/114.0

Steps to reproduce:

1. Use GNOME (latest version, which is 44.2)
2. Use Firefox from Flathub or from the tar.bz2 file from the Mozilla website
3. Now Use Firefox from the repository of a Linux distro such as Fedora
4. Look at the app menu from the top bar

Actual results:

When using Firefox from Flathub or from the Mozilla website, the Firefox icon isn't symbolic. Instead, it's a regular Firefox icon, but desaturated.

Expected results:

Firefox using a symbolic icon in the app menu.

When using Firefox from the Fedora official repo, this is how the icon looks in the app menu.

This is how the icon looks when using Firefox from Flathub or from the Mozilla website.

The Bugbug bot thinks this bug should belong to the 'Core::Widget: Gtk' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Jan, do you have any idea how we can fix this?

Forgot to mention that app menu is going to be removed in GNOME 45, but this problem will continue to exist in 44 and lower.

I've reproduced this issue in Firefox Flatpak 115.0.3 on Ubuntu 22.04.
Setting as NEW.

I think Firefox from Fedora flatpak ships its own icon for that - firefox-symbolic.svg

(In reply to Martin Stránský [:stransky] (ni? me) (PTO, Back on Aug 28) from comment #7)

I think Firefox from Fedora flatpak ships its own icon for that - firefox-symbolic.svg

Yes, it does.

According to UX, the icon used in Fedora is an "official" icon

Do I just need to put it somewhere in the Flatpak?

Yes, it's installed as

/usr/share/icons/hicolor/symbolic/apps/firefox-symbolic.svg

Regular icons are at

/usr/share/icons/hicolor/256x256/apps/firefox.png

(not sure how flatpak handles the paths).