Wayland itches summary

[hansdegoede]

Thank you all for the large amount of feedback I have received after my previous Wayland Itches blog post. I've received over 40 mails, below is an attempt at summarizing all the mails.

Highlights

1. Middle click on title / header bar to lower the Window does not work for native apps. Multiple people have reported this issue to me. A similar issue was fixed for not being able to raise Windows. It should be easy to apply a similar fix for the lowering problem. There are bugs open for this here, here and here.

2. Running graphical apps via sudo or pxexec does not work. There are numerous examples of apps breaking because of this, such as lshw-gui and usbivew. At least for X11 apps this is not that hard to fix. But sofar this has deliberately not been fixed. The reasoning behind this is described in this bug. I agree with the reasoning behind this, but I think it is not pragmatic to immediately disallow all GUI apps to connect when run as root starting today.

We need some sort of transition period. So when I find some time for this, I plan to submit a merge-requests which optionally makes gnome-shell/mutter start Xwayland with an xauth file, like how it is done when running in GNOME on Xorg mode. This will be controlled by a gsettings option, which will probably default to off upstream and then distros can choice to override this for now, giving us a transition period

Requests for features implemented as external programs on X11

There are various features which can be implemented as external programs
on X11, but because of the tighter security need to be integrated into the
compositor with Wayland:

• Hiding of the mouse-cursor when not used à la unclutter-xfixes, xbanish.


• Rotating screen 90 / 270 degrees à la "xrandr -o [left|right]" mostly used through custom hotkeys, possible fix is defining bindable actions for this in gsd-media-keys.


• Mapping actions to mouse buttons à la easystroke


• Some touchscreen's, e.g. so called smart-screens for education, need manual calibration. Under X11 there are some tools to get the callibration matrix for the touchscreen, after which this can be manually applied through xinput. Even under X11 this currently is far from ideal but at least it is possible there.


• Keys Indicator gnome-shell extension. This still works when using Wayland, but only works for apps using Xwayland, it does not work for native apps.


• Some sort of xkill and xdotool utility equivalents would be nice


• The GNOME on screen keyboard is not really suitable for use with apps which are not touch-enabled, as it lacks a way to send ctrl + key, etc. Because of this some users have reported that it is impossible to use alternative on screen keyboards with Wayland. Not being able to use alternative on screen keyboards is by design and IMHO the proper fix here is to improve GNOME's on screen keyboard.

App specific problems

• Citrix ICA Client does not work well with Xwayland


• Eclipse does not work well with Xwayland


• Teamviewer does not work with Wayland. It needs to be updated to use pipewire for screencapturing and the RemoteDesktop portal to inject keyboard and mouse events.


• Various apps lack screenrecording / capture support due to the app not having support for pipewire: gImageReader, green-recorder, OBS studio, peek, screenrecorder, slack


• For apps which do support pipewire, there is not an option to share the contents of a window, other then the window making the request. On Xorg it is possible to share a random window and since pipewire allows sharing the whole desktop I see no security reason why we would not allow sharing another window.


• guake window has incorrect size when using HiDPI scaling, see this issue

Miscellaneous problems

• Mouse cursor is slow / lags


• Drag and drop sometimes does not work, e.g. dragging files into file roller to compress or out of file roller to extract.


• Per keyboard layouts. On X11 after plugging in a keyboard, the layout/keymap for just that one keyboard can be updated manually using xinput, allowing different keyboard layouts for different keyboards when multiple keyboards are connected


• No-title-bar shell extension, X button can be hit unintentionally, see this issue


• Various issues with keyboard layout switching

Hard to fix issues

• Alt-F2, r equivalent (restart the gnome-shell)


• X11 apps running on top of Xwayland do not work well on HiDPI screens


• Push-to-talk (passive key grab on space) does not work in Mumble when using native Wayland apps, see this issue

Problems with other compositors then GNOME3 / mutter

I've also received several reports about issues when using another Wayland compositor as GNOME / mutter (Weston, KDE, Sway). I'm sorry but I have not looked very closely into these reports. I believe that it is great that Linux users have multiple Desktop Environments to choose from and I wish for the other DEs to thrive. But there are only so many hours in a day so I've chosen to mainly focus on GNOME.