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[xcb] Unknown sequence number while appending request (on Python 3.12.8)

Open villares opened this issue 10 months ago • 3 comments

I'm on Manjaro XFCE Linux, today I updated my Python envs and my scripts stopped working so to investigate I picked the "hello" example:

import FreeSimpleGUI as sg                        # Part 1 - The import

layout = [  [sg.Text("What's your name?")],     # Part 2 - The Layout
            [sg.Input()],
            [sg.Button('Ok')] ]

window = sg.Window('Window Title', layout)      # Part 3 - Window Defintion
event, values = window.read()                   # Part 4 - Event loop or Window.read call
print('Hello', values[0], "! Thanks for trying FreeSimpleGUI")
window.close() 

On Python 3.12.8 I get this error message and no GUI:

[xcb] Unknown sequence number while appending request
[xcb] You called XInitThreads, this is not your fault
[xcb] Aborting, sorry about that.
python: xcb_io.c:157: append_pending_request: Assertion `!xcb_xlib_unknown_seq_number' failed.

Process ended with exit code -6.

It works fine on Python 3.10.15 on the same machine:

Image

villares avatar Feb 06 '25 02:02 villares

Thanks for the detailed report.

Given the nature of the error displayed, alongside the fact that this works in other Python versions and only began having problems after updating your Linux Python installation (and presumably its dependencies), this strongly implies to me that the problem may not be something that can be fixed in FreeSimpleGUI, but rather is something that may need to be reported to the maintainers of libX11 or maybe somewhere else.

Though, I won't rule out the possibility that there's something in FreeSimpleGUI that may be at the root of this, at my first look here, I strongly suspect the problem lies elsewhere.

spyoungtech avatar Feb 06 '25 08:02 spyoungtech

For the benefit of other people with this same issue, this might be related to the way that I installed my Python 3.12 (using uv) !

https://github.com/astral-sh/uv/issues/6893

villares avatar Feb 08 '25 21:02 villares

related: https://github.com/astral-sh/python-build-standalone/issues/146 cc @villares (having the same issue with Tk)

astrojuanlu avatar Feb 22 '25 18:02 astrojuanlu

Looks like uv fixed this, yay!

villares avatar Nov 22 '25 22:11 villares