Strange-display-effects-using-WL

I'd try repair the WL7 installation as a first step.

What repair procedure do you suggest ?

I've never seen anything like this, I might even try a complete repair of the OS or at least the .NET installation. What kind of display settings are you using? You could also try modifying them to see if it has any impact.

You might want to check your Microsoft update (or Windows update) control panel to see which .NET modules and video drivers were recently updated by Microsoft. It's possible you may have to roll back one of those updates.

But I agree, this looks like an OS (.NET Core?) issue to me that's not compatible with your video card hardware. Have you talked with the manufacture of your video card? Does their website flag anything about a recent Microsoft video driver update or .NET update?

What other applications are affected? Are they all WPF .NET Core applications (like WL7)?

QUOTE:
What repair procedure do you suggest ?

Choose Repair in Windows Control Panel > Apps > Wealth-Lab 7.

Yet both Glitch and superticker have good points, this can be a video driver issue or broken .NET as well.