Created attachment 465864 [details] Screenshot, side by side comparison with Chromium The following page has an animation of the solar system that uses CSS 3D transforms and animation: https://clixplatform.tiss.edu/softwares/Tools/Solar_System_Animation/en/ The WPE and GTK ports show some of the elements glitching, with some of their parts missing (transparent, mostyl visible on planets) and opacity missing or wrongly applied (mostly noticeable on the text label for Earth as it circles around the sun).
This is reproducible on main (tested 262864@main), both with the WPE and GTK ports; the GTK4 MiniBrowser is shown in the attached screenshot.
Created attachment 465871 [details] Patch to disable depth buffers This is a side effect of enabling depth buffers prematurely by 229846@main. You can check how it looked like by disabling depth buffers. The fundamental problems are tracked by: Bug 217103 – [TextureMapper] A semi-transparent parent layer is rendered as a opaque layer for children layers Bug 217080 – [TextureMapper] Order Independent Transparency support I'm a bit busy now. I'd be grad to review if someone proposes patches for them.