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Try resetting the preferences of Lightroom Classic:  How to reset Lightroom Classic preferences (adobe.com)

It's recommended to backup your preferences before you reset the preferences to the default settings: 

https://helpx.adobe.com/lightroom-classic/kb/preference-file-and-other-file-locations.html

If this doesn't help, switch off the GPU support from the Lightroom preferences and check if that helps to fix the issue. Go to Lightroom > Preferences > Performance tab > Uncheck "Use Graphics Processor" > Restart Lightroom.

https://helpx.adobe.com/lightroom-classic/kb/troubleshoot-gpu.html

If it's help see here Troubleshoot GPU issues | Lightroom Classic (adobe.com) and check the different steps.

If this doesn't help we need more informations about your environment.

Please provide also a copy of your 'System Info'. This can be get from the LrC Help > System Info menu item.

There's a copy button in the System Info dialog. Press this button and paste the info into your next forum post.

Is your system up-to-date? Do you have installed all recent updates and patches for the operating system and the device drivers, especially the graphic driver. If you have a NVidia graphic card installed, make sure that you are using the recent Studio version of the driver, not the Game Ready version.