Escaped already at quickmozview.cpp:205, can be removed. After latest changed to xulrunner I'll test again what kind of blinks I see when height == width. When orientation changes we're going to the new geometry through sequence like: 540x960, 540x540, 960x540. As each change results relayoutting, change to 540x540 adds one extra relayoutting. This is especially bad when web content has responsive layout based on viewport meta tag / available content width.