Thanks for the reply. I should add that I've now just updated to MacOS 26.2 and the problem has disappeared, so it may have been an OS issue that you can now ignore!
I am using Enpass 6.11.17 on MacOS 26. When the window has focus and the cursor is flashing, the entire window flickers in time with the cursor. I've captured this in the video linked here: https://youtu.be/Qln7OLU45vM.
Is anyone else seeing this? Is it a known bug?