User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:2.0b12) Gecko/20100101 Firefox/4.0b12 Build Identifier: Mozilla/5.0 (Windows NT 5.1; rv:2.0b12) Gecko/20100101 Firefox/4.0b12 If you load a webpage with frames, the window resize gripper normally present as a content overlay, does not show. Reproducible: Always Steps to Reproduce: 1. Make sure the add-on bar is off. 2. Load a page with frames Actual Results: Gripper isn't present Expected Results: Gripper should always be present.
Confirmed Mozilla/5.0 (Windows NT 5.1; rv:2.0b13pre) Gecko/20110227 Firefox/4.0b13pre ID:20110227030400
While a regression, I don't think this blocks. We can fix it in a security/stability update. Would definitely consider a safe patch if it materializes before Fx4 gets out the door though.
20160502172042 Mozilla/5.0 (Windows NT 5.1; rv:46.0) Gecko/20100101 Firefox/46.0 20160518030234 Mozilla/5.0 (Windows NT 5.1; rv:49.0) Gecko/20100101 Firefox/49.0 I have tested your issue on latest FF release 46.0.1, latest Nightly build 20160518030234 and managed to reproduce it.