Bug 503041

SUMMARY
When trying to use colorize G’MIC filters interactively with Krita 5.2.9 (freshly installed) on MacOS, I get an error related to opening the interactive display window.
See also this discussion, where another person confirmed it with a different MacOS/Krita specs: https://krita-artists.org/t/can-not-open-interactive-gmic-on-mac-due-to-x-colorize-missing/121382/1

STEPS TO REPRODUCE
1.) From Krita menu, Filter > Start G’MIC - Qt
2.) Search the filter Black & White > Colorize[Interactice] (was also reported with other filters)
3.) Click the Apply button or OK button

OBSERVED RESULT
Error message dialog opened:

```  *** Error in ./fx_colorize_interactive/*repeat/*substitute/x_colorize/ *** Command ‘x_colorize’: No display available.```

EXPECTED RESULT
The interactive window with color selector opens.

SOFTWARE/OS VERSIONS
macOS: 15.2; Darwin (arm64) release 24.2.0
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: 
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 5.15.7

COMMENTS
Likely related to this old Windows bug: https://bugs.kde.org/show_bug.cgi?id=370880 and https://bugs.kde.org/show_bug.cgi?id=369217