I've tried looking this up, but it's hard to describe so I'm not finding any solutions that seem to be the same problem.
So basically this has been happening to several of my photoshop files for weeks now. Usually once a file gets fairly large, but it's also happened on brand new files. When I use the brush tool to start drawing or painting, I get this transparent sort of looking break in the picture and then when I click undo, or even just zoom out sometimes it expands and I'm unable to see the screen or continue working. Once it happens I can sometimes make it go away by continuing to undo or turn off and on layers, but generally nothing fixes it and once it begins on a file it will happen again even after closing and reopening.
I've been having this problem for a few weeks now. It actually began on a different computer and I ignored it, knowing I'd be upgrading soon and it may solve the problem. Obviously it didn't.
I've tried taking the contents I'm working on out of the file into a brand new photoshop file, converting to a psb file format, and I've also tried in the current Photoshop beta and it still happens.