Hi @barton_1995, welcome to the community! Could you share a few more details about the issue? For example, which version of Lightroom are you using? That’ll help us point you in the right direction. Thanks! Alek
*(If you mention me with an @, like @Aleke, I’ll get a notification and can respond faster.)*
Just need a couple of more things. What's the format of the image you're working on? Does this happen only in the Develop module or in the Library module as well?
This can happen because of the GPU preferences. Please go to the Preferences of Lightroom Classic by clicking on the Lightroom Classic menu. Then go to Performance and disable the option to Use Graphics Processor. Once done, relaunch the app to check if it makes a difference.