User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3218.0 Safari/537.36 Steps to reproduce: macOS 10.12.6 57.0a1 (2017-09-17) (64-Bit) 1.) CMD-N to open a New Tab Page Actual results: Gear, Firefox Logo, Search Bar, etc. are flickering Expected results: They should not flicker. At least the Gear and the Firefox Logo should not flicker, if you want a blank page. This is disruptive.

This also flickers on New Private Tabs. Please see enclosed screencast. Can this be addressed also with this report or should I file separate report for it? Thanks.

File a separate thing for private browsing new tabs. Note that there's bug 1379587 but looks like the video is showing the purple background then text appears.

(In reply to Ed Lee :Mardak from comment #2) > File a separate thing for private browsing new tabs. Note that there's bug > 1379587 but looks like the video is showing the purple background then text > appears. Done: Bug 1400990 Thank you!

If we want to fix this, we'll need to improve newtab preloading, and possibly warm up the preloaded new tab so that we are ready to switch to it immediately.

Bug 1417155 will make it possible to have new tabs load about:blank to be entirely blank. As for the flicker, it's what's shown before a new tab is switched to and is mainly noticeable from an existing new tab page.