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***

SUMMARY
On older video card hardware (i915) there is some broken rendering with OpenGL composting. 
In journalctl I see the following information:

Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to link shader program: error: Exceeded max ALU instructions (106/64)
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to build graphics pipeline state
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to link shader program: error: Exceeded max ALU instructions (106/64)
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to build graphics pipeline state
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to link shader program: error: Exceeded max ALU instructions (106/64)
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to build graphics pipeline state
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to link shader program: error: Exceeded max ALU instructions (106/64)
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to build graphics pipeline state
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to link shader program: error: Exceeded max ALU instructions (106/64)
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to build graphics pipeline state
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to link shader program: error: Exceeded max ALU instructions (106/64)
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to build graphics pipeline state
Jun 26 13:12:39 mrichan plasmashell[1424]: Failed to link shader program: error: Exceeded max ALU instructions (106/64)
Jun 26 13:15:13 mrichan systemsettings[1774]: Failed to link shader program: error: Exceeded max ALU instructions (77/64)
Jun 26 13:15:13 mrichan systemsettings[1774]: Failed to build graphics pipeline state
Jun 26 13:15:13 mrichan systemsettings[1774]: Failed to link shader program: error: Exceeded max ALU instructions (77/64)
Jun 26 13:15:13 mrichan systemsettings[1774]: Failed to build graphics pipeline state



STEPS TO REPRODUCE
1. Install KDE 6.1.1 (or older version) on hardware with video card i915
2. Check the logs 

OBSERVED RESULT
Issues with graphics rendering.
Also separate issue with login screen SDDM without text. I have created separate bug report: https://github.com/sddm/sddm/issues/1958

EXPECTED RESULT
No rendering issues 

SOFTWARE/OS VERSIONS 
Linux/KDE Plasma: Gentoo
(available in About System)
KDE Plasma Version: 6.1.1
KDE Frameworks Version: 6.3.0 
Qt Version: 6.7.1

ADDITIONAL INFORMATION