On Touchscreens Touch Screen Button stops working after using once.

[rexackermann]

Describe the Bug

On touch screen the button works once and the not again.Not even using mouse.Keyboard Shortcut works but the button simmply would't respond until I turn it off and turn back on again.

Steps to reproduce the behavior:

1. Install extension
2. Go to Settings > Menu Editor > Example Menu
3. Toggle Touch Screen Button on
4. Use extension using touch screen once
5. Then it doesn't work again

Expected Behavior

Should not stop working after using once.

System

Please complete the following information:

• Linux distribution [e.g. Fedora 37]
• Fly-Pie version [18]
• GNOME Shell version: [43.3]

[Schneegans]

Hey there, thanks for the report! Does this happen on X11, Wayland, or both?

[rexackermann]

Hey there, thanks for the report! Does this happen on X11, Wayland, or both?

Works on wayland ,only happens on x11.

[Schneegans]

Ok, thanks. I am currently busy preparing a major release for Burn-My-Windows. Hopefully I'll find the time thereafter to look into this!

[Schneegans]

I can indeed reproduce this. I will explore some more, but I get the feeling that this is a regression in GNOME Shell's touch handling. I am pretty sure that this used to work properly in GNOME 42.

While testing, I also noticed that I cannot summon the ordinary desktop context menu under X11 using touch input. On Wayland, I can long-press the desktop to open the context menu. On X11, nothing happens. Is this the case for you as well?

[Schneegans]

Btw, I get the same behavior in GNOME 44.

[claudiusraphael]

Don't know if this helps tracking it down, but Ubuntu and derivative (still) often use Synaptics/Elan/etc device-drivers for touchpad and touchscreens in laptops/tablets/convertibles under X11 instead of using libinput. Under Wayland this is not a thing so there these mostly work. On fedora this behavior can pop up when enabling 3rd-party repos and firmwares and (due to app defaults based on that) allowing them to be installed as a recommended dependency.

You may want to check the general info-page on libinput.

One possible reason in many cases is to be found in the FAQ:

Why does my touchpad lose track of touches
The most common cause for this is an incorrect pressure threshold range. See Touchpad pressure-based touch detection for more info.

Some touch-controllers trip into faulty processing of touch-events if the threshold-pressure is at the limit - kinda as if it overflows and then disables tracking because it "thinks" it is faulty or for example as part of an "accidental-touch-detection".

Some devices (mostly tablets/chromebooks after 2018) also offer glove-mode aka high-sensibility, which is leading to a similar error when not used with gloves. This is the vice-versa-case, because this happens due to glove-mode being enabled by default by the generic driver and/or the firmware.

Hope this helps digging deeper.