Definitely think it should be filed as a bug report. I’ve been doing some digging and every recent instance of this occurring has been on 5.1 SM6. Both DX12 and Vulkan are having reported issues. Wish I had a better idea in the meantime, but if it’s just widgets there’s not to go on. Could be slate itself, just UMG, or a hyperspecific hardware/software snafu, etc.