For the past little while, we have been tracking some interesting WebRender bugs that people are reporting in release. Despite best efforts, we have been unable to determine clear steps to reproduce these issues and have been unable to find a fix for them. Today we are announcing a special challenge to the community – help us track down steps to reproduce (a.k.a STR) for this bug and you will win some special, limited edition Firefox Graphics team swag! Read on for more details if you are interested in participating.

What we know so far about the bug:

Late last year we started seeing reports of random UI glitching bugs that people were seeing in release. You can check out some of the reports on Bugzilla. Here is what we know so far about this bug:

At seemingly random intervals, either two things seem to happen: The text in the UI and content area of the browser seem to glitch out Scrolling through the page or mousing over the affected area seems to fix it Or black boxes appear on the screen and also seem to disappear after scrolling around



Glitches!

Black boxes!

The majority of the reports we have seen so far have come from people using NVIDIA graphics cards, although we have seen reports come in of this happening on Intel and AMD as well. That could be though because the majority of the people we have officially shipped WR to in release are on NVIDIA cards.

There doesn’t seem to be one clear driver version correlated to this bug, so we are not sure if it is a driver bug.

All reporters so far have been using Windows 10

No one who has reported the bug thus far has been able to determine clear and consistent STR, and no one on the Graphics team has found a way to reproduce it either. We all use WebRender daily and none of us have encountered the bug.

How can you help?

Without having a way to reliably reproduce this bug, we are at a loss on how to solve it. So we decided to hold a challenge to engage the community further to help us understand this bug better. If you are interested in helping us get to the root of this tricky bug, please do the following:

Download Firefox Nightly (if you don’t already use it)

Ideally you are using Windows 10 (but if you see this bug on other platforms, we are interested in hearing about it!)

Ensure WebRender is enabled Go to about:config and set gfx.webrender.all to true, then restart your browser

If you encounter the bug, help us by filing a bug in Bugzilla with the following details: What website are you on when the bug happens? Does it seem to happen when specific actions are taken? How frequently does the bug happen and can you ‘make’ it happen? Attach the contents of your about:support as a text file

The main thing we really need are consistent steps that result in the bug showing up. We will send some limited edition Graphics swag to the first 3 bug reporters who can give us consistent STR!

Even if you can’t easily find STR, we are still interested in hearing about whether you see this bug!

Challenge guidelines

The winners of this challenge will be chosen based on the following criteria:

The bug report contains clear and repeatable steps to make the bug happen This can include things like having a specific hardware configuration, using certain add ons and browsing certain sites – literally anything as long as it can reliably and consistently cause the bug to appear BONUS: A member of the Graphics team can follow your steps and can also make the bug appear

We will choose the first 3 reporters who can meet this criteria (we say 3 because it is possible there is more than one bug and more than one way to reproduce it)

(we say 3 because it is possible there is more than one bug and more than one way to reproduce it) Winners will receive special limited edition Graphics Team swag! (t-shirt and stickers)

Update: we have created the channel #gfx-wr-glitch:mozilla.org on Matrix so you can ask questions/chat with us there. For more info about how to joing Matrix, check out: https://wiki.mozilla.org/Matrix