Lubuntu 21.04 - GIMP crashes

[neblaz]

lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 21.04
Release: 21.04
Codename: hirsute

GIMP 2.10.22 installed from Discover.
Launching it from command line with gimp

Opening a JPG file, using the Rectangular Selection Tool selecting a portion of the image. Then right clicking on the selected portion to open the context menue > Edit > Cut results in GIMP crashing.
The output on the command line is:

The program ‘gimp’ received an X Window System error.
This probably reflects a bug in the program.
The error was ‘BadWindow (invalid Window parameter)’.
(Details: serial 79211 error_code 3 request_code 18 minor_code 0)
(Note to programmers: normally, X errors are reported asynchronously;
that is, you will receive the error a while after causing it.
To debug your program, run it with the --sync command line
option to change this behavior. You can then get a meaningful
backtrace from your debugger if you break on the gdk_x_error() function.)

(script-fu:11443): LibGimpBase-WARNING **: 13:03:53.508: script-fu: gimp_wire_read(): error

Folllowing the given instruction launching GIMP with gimp --sync and performing the same steps, after the Cut operation GIMP hangs, nothing happens from then on. Termination with Ctrl + C result in the given output after ^C:

^Cgimp: terminated: Interrupt
gimp: Gimp-Core-CRITICAL: gimp_item_get_ID: assertion ‘GIMP_IS_ITEM (item)’ failed
/usr/lib/gimp/2.0/plug-ins/script-fu/script-fu terminated: Interrupt

On Ubuntu this simple image operation problem doesn’t happen, looks like it is related to Lubuntu.

[neblaz]

I made the following change on Lubuntu.

Preferences > LXQt settings > Window Effects
Change from GLX (OpenGL) to X Render

Now when I perform the same steps, after Cut in command line:
using gegl copy

It works now, GIMP doesn’t crash.
When I quit GIMP the output is:

gimp: GEGL-WARNING: (…/gegl/buffer/gegl-tile-handler-cache.c:1076):gegl_tile_cache_destroy: runtime check failed: (g_queue_is_empty (&cache_queue))
EEEEeEeek! 1 GeglBuffers leaked

Don’t know if this is something critical, at least GIMP doesn’t crash on the described image manipulation operation.

Can someone explain, what to use in Windows Effects. Isn’t GLX (OpenGL) the preferred option?
I have installed Mesa 3D:

glxinfo | grep OpenGL
OpenGL vendor string: Intel
OpenGL renderer string: Mesa Intel(R) UHD Graphics 600 (GLK 2)
OpenGL core profile version string: 4.6 (Core Profile) Mesa 21.0.1
OpenGL core profile shading language version string: 4.60
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 4.6 (Compatibility Profile) Mesa 21.0.1
OpenGL shading language version string: 4.60
OpenGL context flags: (none)
OpenGL profile mask: compatibility profile
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.2 Mesa 21.0.1
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.20
OpenGL ES profile extensions: