Unfortunately, the latest version 104.0.4944.33 is bad - it runs very slowly.

Excuse me - i apologize. Actually 104.0.4944.33 works even better than 104.0.4944.28 - the issue turns out to be in the graphics drivers on one of the devices. Now everything works fine after a reinstallation.

Backlinking the issue on another forum with workaround that worked for me (disabling Qt) https://forum.artixlinux.org/index.php/topic,5847.0.html

Finally, that works for me - now opera runs on my devices with Debian LXQt again. Thanks for the reference.

Unfortunately, the latest version 104.0.4944.33 is bad - it runs very slowly.

Backlinking the issue on another forum with workaround that worked for me (disabling Qt) https://forum.artixlinux.org/index.php/topic,5847.0.html

So as with this - add this to the launch settings (?):

--disable-features=AllowQt

I read thru that thread - that's an easy fix, but I read others found more involved fixes.

And I see the issue is reported by a number of LXQT users, but one instance of KDE.

Some folks solved it by running XFCE (mostly as a test, which I suggested),

It appears to be an issue with QT, so yea, folks who use LXQT will mostly be affected. (though some did a workaround with gtk settings).

So Not an Opera issue, as the OP alludes to.

It doesn't work in our case because the issue is related to a basal incompatibility between the modern chromium-based browsers' GUI and GLib-GObject library in Debian 11 LXQt.

So, it works using Cinnamon (mentioned by @pindos) on Debian. (and my environment: Tumbleweed using KDE Plasma).

But I agree, seems an obvious issue with this particular LXQT implementation on Debian, especially since other Chromium based browsers are affected.

A quick test would be to login using another DM, then launch Opera.

the issue is related to a basal incompatibility between the modern chromium-based browsers' GUI and GLib-GObject library in Debian 11 LXQt.

Maybe you have to inform the developers of LXQt-environment about this bug? The latest version of Opera works fine on Debian 11.7.

There are times when it seems all chromium-based browsers , when updated, render nothing, i.e., there is nothing shown in its window.

THIS IS the solution that works for everyone - keep in mind, this might NOT be the solution for your problem, but doing this will do no harm.

Open a command line window and execute this command

find ~/ -type d -name GPUCache

The list of files you see are simply cached data, that really doesn't matter ... however, for whatever reason, between version upgrades, they are corrupted.

So the easiest solution is to delete those - as I wrote, removing will do no harm. The following Linux command will delete all those , but if you prefer, rename that sub-directory to "GPUCache-backup" if you prefer

Reminder - this might be a long-shot solution for you, but it will not cause any issues - run this to clear:

find ~/ -type d -name GPUCache -exec rm -rf {} +

Hope it helps !

It doesn't work in our case because the issue is related to a basal incompatibility between the modern chromium-based browsers' GUI and GLib-GObject library in Debian 11 LXQt.

THIS IS the solution that works for everyone - keep in mind, this might NOT be the solution for your problem, but doing this will do no harm.

Open a command line window and execute this command

find ~/ -type d -name GPUCache

The list of files you see are simply cached data, that really doesn't matter ... however, for whatever reason, between version upgrades, they are corrupted.

So the easiest solution is to delete those - as I wrote, removing will do no harm. The following Linux command will delete all those , but if you prefer, rename that sub-directory to "GPUCache-backup" if you prefer

Reminder - this might be a long-shot solution for you, but it will not cause any issues - run this to clear:

find ~/ -type d -name GPUCache -exec rm -rf {} +

Hope it helps !

If you haven't already, you should post the issue in a Debian forum ... most likely related to the/your Deb environment.

No probs here on openSuse Tumbleweed, using a Flatpak.

For others, you can download an older working version from https://get.opera.com/ftp/pub/opera/desktop/101.0.4843.58/linux/
Or pick your favorite version here: https://get.opera.com/ftp/pub/opera/desktop/

$ uname -a
Linux ### 6.4.8-060408-generic #202308041557 SMP PREEMPT_DYNAMIC Fri Aug 4 16:03:00 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

opera-stable 102.0.4880.33
opera-beta 102.0.4880.10
opera-developer 103.0.4899.0

libglib2.0-dev 2.74.3-0ubuntu1.2
gir1.2-glib-2.0 1.74.0-2

[122624:122624:0901/044703.097085:ERROR:browser_main_loop.cc(286)] GLib-GObject: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed
[122624:122624:0901/044703.097112:ERROR:browser_main_loop.cc(286)] GLib-GObject: g_type_interface_add_prerequisite: assertion 'G_TYPE_IS_INTERFACE (interface_type)' failed
[122624:122624:0901/044703.097129:ERROR:browser_main_loop.cc(286)] GLib: g_once_init_leave: assertion 'result != 0' failed
[122624:122624:0901/044703.097137:ERROR:browser_main_loop.cc(286)] GLib-GObject: g_type_add_interface_static: assertion 'G_TYPE_IS_INSTANTIATABLE (instance_type)' failed
[122624:122624:0901/044703.097145:ERROR:browser_main_loop.cc(286)] GLib-GObject: g_type_register_static: assertion 'parent_type > 0' failed

It is already done - see the original post.

Open a command line window and execute "opera".

That might display some error messages you can capture and report back.