Pinch to zoom not working on Wayland on Jammy

[Umayr Saghir]

Firefox running within snap confinement is unable to use the pinch to zoom gesture on 22.04. This is a regression as it does work on 21.10. I had been following https://bugs.launchpad.net/bugs/1964541 as it was suspected that these two issues were linked, however I am using the updated mutter released as a fix for the drag and drop bug but this didn't result in a fix for pinch to zoom. Pinch to zoom does work when using Firefox from the official tarball with the variable MOZ_ENABLE_WAYLAND=1 set.

Originally reported on the snapcraft forum:https://forum.snapcraft.io/t/firefox-pinch-to-zoom-not-working-on-22-04/29391

Screen recording attached showing pinch to zoom not working on snap firefox and comparing with the gesture working on mozilla tarball firefox with libinput debug-gui showing the pinch gesture

Description: Ubuntu Jammy Jellyfish (development branch)
Release: 22.04

$ snap info firefox
name: firefox
summary: Mozilla Firefox web browser
publisher: Mozilla✓
store-url: https://snapcraft.io/firefox
contact: https://support.mozilla.org/kb/file-bug-report-or-feature-request-mozilla
license: unset
description: |
  Firefox is a powerful, extensible web browser with support for modern web
  application technologies.
commands:
  - firefox
snap-id: 3wdHCAVyZEmYsCMFDE9qt92UV8rC8Wdk
tracking: latest/beta
refresh-date: 2 days ago, at 18:06 BST
channels:
  latest/stable: 99.0.1-1 2022-04-13 (1232) 163MB -
  latest/candidate: 99.0.1-1 2022-04-12 (1232) 163MB -
  latest/beta: 100.0b6-1 2022-04-15 (1244) 163MB -
  latest/edge: 101.0a1 2022-04-15 (1243) 180MB -
  esr/stable: 91.8.0esr-1 2022-04-05 (1184) 161MB -
  esr/candidate: 91.8.0esr-1 2022-03-30 (1184) 161MB -
  esr/beta: ↑
  esr/edge: ↑
installed: 100.0b5-1 (1236) 163MB -

mutter:
  Installed: (none)
  Candidate: 42.0-3ubuntu2
  Version table:
     42.0-3ubuntu2 500
        500 http://gb.archive.ubuntu.com/ubuntu jammy/universe amd64 Packages

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Umayr Saghir (nightmayr)]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:100.0) Gecko/20100101 Firefox/100.0

Steps to reproduce:

Install the Firefox snap on Ubuntu 22.04 (should be preinstalled), switch to the beta channel (snap refresh firefox --beta) as this uses the Wayland backend (stable currently uses XWayland). Open Firefox and attempt to use pinch to zoom gestures.

Actual results:

The content of webpages fails to zoom in when the pinch to zoom gesture is used. This previously was working on Ubuntu 22.10 using the Firefox snap.

Note this did apply to the stable channel version 99 before it was changed from using Wayland to XWayland.

Expected results:

The gesture should have been recognised and the content of the web page should have zoomed in.

[Umayr Saghir (nightmayr)]

(In reply to Umayr Saghir from comment #0)
> User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:100.0) Gecko/20100101 Firefox/100.0
>
> Steps to reproduce:
>
> Install the Firefox snap on Ubuntu 22.04 (should be preinstalled), switch to the beta channel (snap refresh firefox --beta) as this uses the Wayland backend (stable currently uses XWayland). Open Firefox and attempt to use pinch to zoom gestures.
>
>
> Actual results:
>
> The content of webpages fails to zoom in when the pinch to zoom gesture is used. This previously was working on Ubuntu 21.10 using the Firefox snap.
>
> Note this did apply to the stable channel version 99 before it was changed from using Wayland to XWayland.
>
>
> Expected results:
>
> The gesture should have been recognised and the content of the web page should have zoomed in.

[Umayr Saghir (nightmayr)]

Correction: Wrote "This previously was working on Ubuntu 22.10" in the original comment. Obviously meant 21.10 Impish Indri.

[Umayr Saghir (nightmayr)]

Bug created under Mozilla bug tracker: https://bugzilla.mozilla.org/show_bug.cgi?id=1766042

[Sebastien Bacher (seb128)]

Thanks

[Umayr Saghir (nightmayr)]

Not sure if something changed recently within Firefox, but Pinch to zoom is working again for me.

Snapd: 2.55.5 (revision 15904)
Firefox: 102.0b2-1 (revision 1415 (beta channel))

[Olivier Tilloy (osomon)]

It looks like the difference might be in using the Wayland backend (default in the beta and edge channels), versus being an XWayland client (default in the stable channel).

Can you switch back to the stable channel, and test again with `MOZ_ENABLE_WAYLAND=1` ?

[Umayr Saghir (nightmayr)]

(In reply to Olivier Tilloy from comment #4)
> It looks like the difference might be in using the Wayland backend (default in the beta and edge channels), versus being an XWayland client (default in the stable channel).
>
> Can you switch back to the stable channel, and test again with `MOZ_ENABLE_WAYLAND=1` ?

The snap was previously failing to recognise the gesture with the Wayland backend on the beta channel a few weeks back (switched to beta roughly around the time stable was made to default to XWayland).

Running `MOZ_ENABLE_WAYLAND=1 firefox` when using the stable channel version now recognises the gesture.

[Lissyx+mozillians (lissyx+mozillians)]

Looks like we can consider this FIXED ? Please Reopen if that is not the case.

[Utku BERBEROĞLU (boluluutku)]

This issue is not fixed. Today, i changed to Firefox Deb package for the experiment. Zoom to pinch works for deb package from Mozilla PPA. Its also works for Gnome Web. I am on the Wayland session.

Ubuntu 22.04.3
Mesa Intel® UHD Graphics 620 (WHL GT2)

I can give additional information if requested.

[m.hesselink (m-hesselink)]

Can confirm.

Zoom to pinch not working with Firefox snap on Wayland. Two finger scroll does work properly.

Ubuntu 22.04.3 LTS

snap list | grep firefox
firefox 118.0.1-1 3206 latest/stable/… mozilla** -

Mesa Intel® Xe Graphics (TGL GT2)