User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:60.0) Gecko/20100101 Firefox/60.0 Build ID: 20180129100406 Steps to reproduce: Activate WebRender. Visit www.computerbase.de/forum and pick a subforum, e.g. https://www.computerbase.de/forum/forumdisplay.php?f=49 Actual results: The grey lines that separate the individual threads are rendered in differing strenghts with WebRender enabled: https://abload.de/img/unevenqpobe.jpg Expected results: The grey lines that separate the individual threads are rendered evenly across the page: https://abload.de/img/even4jqz8.jpg

Thanks! Confirmed in Nightly 60 x64 20180129100406 de_DE @ Debian Testing (KDE, Radeon RX480). > <div class="rating0 nonsticky clearfix"> has: > background: linear-gradient(to bottom,#ffffff 0%,#f5f5f5 100%); If I set the background of > <div class="threadlist-wrapper clearfix"> to red, the lower edge of the gradient flickers red (like a border-bottom: 1px solid red) when scrolling down and remains sometimes. This reminds me a bit of bug 1432046, but doesn't seem to be the same.

I am sorry. Either this is intermittent or I don't have found exact STR. :(

Debian Testing (KDE, Radeon RX480) Slowly autoscrolling down at 150% zoom. mozregression --launch 2018-01-30 --pref gfx.webrender.all:true general.autoScroll:true startup.homepage_welcome_url:"https://www.computerbase.de/forum/forumdisplay.php?f=93"

mozregression --good 2017-08-15 --bad 2017-10-01 --pref layers.acceleration.force-enabled:true gfx.webrender.enabled:true gfx.webrendest.enabled:true gfx.webrender.layers-free:true gfx.webrender.blob-images:true image.mem.shared:true layout.display-list.retain:false general.autoScroll:true startup.homepage_welcome_url:"https://www.computerbase.de/forum/forumdisplay.php?f=93" > 14:08.84 INFO: Last good revision: 3dbe64e08fd0de104d205d2c91813992f78c6c6d > 14:08.84 INFO: First bad revision: fa8562b32dae3315975ec8387fd70861290121e4 > 14:08.84 INFO: Pushlog: > https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=3dbe64e08fd0de104d205d2c91813992f78c6c6d&tochange=fa8562b32dae3315975ec8387fd70861290121e4 (2017-09-13) > fa8562b32dae Ethan Lin — Bug 1393077 - Part3. Modify annotations for affected testcases. r=kats > fc237de487fd Ethan Lin — Bug 1393077 - Part2. Round the offset for the fallback. r=kats > fa2ccc95cf0c Ethan Lin — Bug 1393077 - Part1. Round the transformed rectangles and transformed points in StackingContextHelper. r=kats

Reconfirmed. Win10 1803 (GeForce GTX 1060), 2560x1440 (Dell U2515H)

I can't reproduce this anymore. It renders fine on my Radeon R9 390 And Intel HD 520. The Computerbase forum will be turned off in a few days anyway (switching to Xenforo), which will make STR obsolete.

Fixed by bug 1451439.