User Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 Build ID: 20150725030209 Steps to reproduce: 1) Enter www.securitytube.net 2) Click on the small rectangle that says "Close sidebar". 3) Observe the jank. * A performance recording confirms there is a paint that takes a whooping ~20ms on my high end machine. Actual results: Closing the sidebar is janky because of excessive time in painting. Expected results: Smooth transition when scrolling the side bar.
Note: This was tested with e10s enabled. Turning off e10s yields a lot worse performance.
2 years ago
I'm focusing my efforts on general APZ performance so I don't really have time to investigate. 20ms isn't great but if we do a large change to our layer tree then it's not unreasonable.