User Agent: Mozilla/5.0 (Windows NT 10.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.82 Safari/537.36 Vivaldi/1.10.829.3 Steps to reproduce: When e10s is off (FF 53)switching to a new tab is instantly when closing tabs quickly with images in fresh profile but when e10s is on it's jerky/janky. Say have images opened in ten tabs and close them one by one using Ctrl+w and new tab content displayed instantly. With e10s on the new tab flashes or redrawn just like for a second which makes it feel a lot slower and disrupt unlike before the tab closed and content there without any flicks or black/blink tabs or redrawing. Just open links from here and the close tabs to see what trying to say The way Photon is going to improve performance this is a major thing to fix. Switching tabs like ff52 should be improved and switching like in e10s ff55 should be removed or on par with ff52

Can reproduce the problem,there is definitely a blink or redraw or something like that cpu usage spike up also and all cores start to run With e10s on

no high cpu usage or blinks or redraws with e10s off

did some profiling might help https://perfht.ml/2qWA8Ia e10s off https://perfht.ml/2qWcwU3 e10s sold start https://perfht.ml/2qWAUVA e10s warm start

Excuse me, but if you want to report a bug properly you need to specify what settings you use. Judging by the attachment 8865723 [details] , you have browser.tabs.animate set to false. White flashes when closing tabs with browser.tabs.animate set to false is a known bug reported here: https://bugzilla.mozilla.org/show_bug.cgi?id=1237654 So to get rid of this issue just set browser.tabs.animate to true.

(In reply to ajfhajf from comment #5) > Excuse me, but if you want to report a bug properly you need to specify what > settings you use. Judging by the attachment 8865723 [details] , you have > browser.tabs.animate set to false. White flashes when closing tabs with > browser.tabs.animate set to false is a known bug reported here: > https://bugzilla.mozilla.org/show_bug.cgi?id=1237654 > > So to get rid of this issue just set browser.tabs.animate to true. Original reporter here! had tested with new profile with defaults, the person above you was just verifying that it can be reproduced.

This bug is the duplicate of the bug #1237654, so performance and blinks/flashes will be fixed when bug #1237654 will also be fixed. The workaround for this is setting this value "browser.tabs.animate" [Fx54] or "toolkit.cosmeticAnimations.enabled" [Fx55] to "true" (which is default) in about:config

(In reply to Virtual_ManPL [:Virtual] - (please needinfo? me - so I will see your comment/reply/question/etc.) from comment #7) > This bug is the duplicate of the bug #1237654, > so performance and blinks/flashes will be fixed when bug #1237654 will also > be fixed. > > The workaround for this is setting this value "browser.tabs.animate" [Fx54] > or "toolkit.cosmeticAnimations.enabled" [Fx55] to "true" (which is default) > in about:config NO this is a different bug as even if browser.tabs.animate on true It's the tab content(to be precise the images which blink) Try fullscreen so tabs are hidden and then close tabs with kb, the content/images of tabs flicker badly for a few seconds, see attachments and ignore tabs and focus on contents.

(In reply to jigsawmode from comment #8) > It's the tab content(to be precise the images which blink) > > Try fullscreen so tabs are hidden and then close tabs with kb, > the content/images of tabs flicker badly for a few seconds, see attachments > and ignore tabs and focus on contents. The blinking issue is tracked in bug #1237654. I can't reproduce the flickering tabs for few seconds, nor I see it in attached screencasts, I just only can reproduce the flashing/bling full tab content. Is it reproducible with: - with clean new fresh profile without any addons (extensions, plugins, themes, etc.) - Safe Mode - in other operating system on same PC - on other PC

(In reply to Virtual_ManPL [:Virtual] - (please needinfo? me - so I will see your comment/reply/question/etc.) from comment #9) > (In reply to jigsawmode from comment #8) > > It's the tab content(to be precise the images which blink) > > > > Try fullscreen so tabs are hidden and then close tabs with kb, > > the content/images of tabs flicker badly for a few seconds, see attachments > > and ignore tabs and focus on contents. > > The blinking issue is tracked in bug #1237654. > I can't reproduce the flickering tabs for few seconds, nor I see it in > attached screencasts, > I just only can reproduce the flashing/bling full tab content. > > Is it reproducible with: > - with clean new fresh profile without any addons (extensions, plugins, > themes, etc.) > - Safe Mode > - in other operating system on same PC > - on other PC think he means that the page blinks, will try to test this and see if it's different.

(In reply to jaruvova from comment #10) > think he means that the page blinks, So that's for sure bug #1237654. (In reply to jaruvova from comment #10) > will try to test this and see if it's different. Using multiple accounts won't bring credibility, so I will wait for real OP answer.

(In reply to Virtual_ManPL [:Virtual] - (please needinfo? me - so I will see your comment/reply/question/etc.) from comment #11) > (In reply to jaruvova from comment #10) > > think he means that the page blinks, > So that's for sure bug #1237654. Okay mightbe but this poppedup switching icon to svg instead of png > (In reply to jaruvova from comment #10) > > will try to test this and see if it's different. > Using multiple accounts won't bring credibility, > so I will wait for real OP answer. What?