1371932 - Firefox should set _NET_WM_ICON_NAME to mozicon128.png to ensure that high-res icons are appropriately displayed on Linux

Status: RESOLVED DUPLICATE of bug 1414881

(Core :: Widget: Gtk, defect)

Description

[Nate Graham]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:53.0) Gecko/20100101 Firefox/53.0
Build ID: 20170524174214

Steps to reproduce:

1. Install Firefox on Kubuntu 17.04
2. Do NOT install any 3rd party icons for Firefox in /usr/share/icons
3. Use the Plasma Large Icons style for the Task Switcher (System Settings > Window Management > Task Switcher > Main > Large icons)
4. Hit alt-tab


Actual results:

The alt-tab window switcher displays Firefox's icon as an ugly scaled-up 48x48 icon. I've attached a screenshot showing the problem.


Expected results:

The 128x128 icon (mozicon128.png) should be used instead, so that the large icon is pretty and not pixelated.

The problem occurs because Firefox does not set _NET_WM_ICON_NAME to mozicon128.png. Because of this, the window manager it not aware of the high-res icon, and is forced to display a scaled-up version of the largest icon it is aware of--the 48x48 version. This can be verified by running `xprop` and targeting Firefox's main window; you will see that the largest icon it knows about is only 48x48.

For more information and context, see the following:
https://bugs.kde.org/show_bug.cgi?id=351055
https://specifications.freedesktop.org/wm-spec/1.4/ar01s05.html

Comment 1

[Nate Graham]

Attachment: Firefox and Thunderbird with pixelated icon.png

Comment 2

[Strangiato]

Firefox 57 icon is also pixelated in alt+tab menu on KDE Plasma.

Comment 3

[Johan Lorenzo [:jlorenzo]]

This might have been fixed in Firefox 59, thanks to bug 1414881. Could you verify if the latest beta (or nightly) is fixed for you, pointedstick?

Comment 4

[Nate Graham]

Confirming! The icon is nice and sharp with the nightly build for Firefox 59. Can't wait to see the real icon rendered as nicely. I hope Thunderbird can get the same treatment soon, too (https://bugzilla.mozilla.org/show_bug.cgi?id=1371931).

Should we close this now?

Comment 5

[Johan Lorenzo [:jlorenzo]]

Awesome! Thank you very much for the check. Let me close the bug, then.