Just installed 4.3.2rc1 on my iPad 3 (iOS 7.0.3 [11B511]). When I first launched, 1Password asked how I wanted to sync, I said Dropbox. And I think at that point I was taken to the main listing screen under "Categories" - and something that I'm pretty sure is a scroll bar was flickering in a way that looked worrying. I think it was the scroll bar for the items listing. My guess is that this was caused by it accessing my 1Password data for the first time.
I haven't seen this again so I guess it's okay now.