CPU is AMD Ryzen 7 7800X3D 8-Core Processor

Let me go see what happens.

I'm not able to replicate the issue. see screenshot Have you tried a different Desktop and X11? Did you try with Firefox in Troubleshoot Mode? Try downloading Firefox from Mozilla. Download, unzip, and run firefox-bin from the folder and see if you have the same issue. https://www.mozilla.org/en-US/firefox/all/#product-desktop-release

Which nvidia card and driver version?'

Operating System: openSUSE Tumbleweed 20240811 KDE Plasma Version: 6.1.4 KDE Frameworks Version: 6.5.0 Qt Version: 6.7.2 Kernel Version: 6.10.3-1-default (64-bit) Graphics Platform: X11 Processors: 12 × Intel® Core™ i7-9850H CPU @ 2.60GHz Memory: 125.1 GiB of RAM Graphics Processor: Mesa Intel® UHD Graphics 630 Manufacturer: HP Product Name: HP ZBook 17 G6

I have tried using --safe-mode and I was unable to reproduce the issue. Using only weston as the windows manager the issue still appears. You can see that from the screen shot. Using a fedora boot USB has the same issue. You can see this with the characters incorrectly rendered.

This only happens with this GPU (the on die one). I added an old video card and the problem doesn't happen when using that video card AMD RX480 (same kernel driver, different mesa):

Please note, it wasn't clear but the rendering sometimes resolves itself on a redraw, eg via scrolling. I have read other posts about as similar problem on reddit but I don't believe that this is a hardware problem. Unfortunately, I have been waiting 8 months with several version of mesa, kernels and firefox and the problem that on intermittently appears with firefox and only firefox (not other apps) hasn't been resolved.

Kernel version 6.10.6

GPU #1 Active Yes Description AMD Radeon Graphics (radeonsi, raphael_mendocino, LLVM 18.1.8, DRM 3.57, 6.10.6) Vendor ID 0x1002 Device ID 0x164e Driver Vendor mesa/radeonsi Driver Version 24.2.0.0 RAM 0

This only happens with this GPU (the on die one). I added an old video card and the problem doesn't happen when using that video card AMD RX480 (same kernel driver, different mesa):

Please note, it wasn't clear but the rendering sometimes resolves itself on a redraw, eg via scrolling. I have read other posts about as similar problem on reddit but I don't believe that this is a hardware problem. Unfortunately, I have been waiting 8 months with several version of mesa, kernels and firefox and the problem that on intermittently appears with firefox and only firefox (not other apps) hasn't been resolved.

I was going to mention Graphics and driver version.

You can check for issues with fonts.

You can right-click and select "Inspect" to open the built-in Inspector with this element selected.

• https://firefox-source-docs.mozilla.org/devtools-user/page_inspector/how_to/open_the_inspector/
• https://firefox-source-docs.mozilla.org/devtools-user/page_inspector/how_to/examine_and_edit_html/

You can check in the Rules tab in the right panel in the Inspector what font-family is used for selected text. You can check in the Fonts tab in the right panel in the Inspector what font is actually used because Firefox might be using a different font than specified by the website, if necessary expand "All fonts..."#. If the Fonts tab is hidden, click the Down arrow at the right end.

• https://firefox-source-docs.mozilla.org/devtools-user/page_inspector/how_to/edit_fonts/

Are you saying that I don't have the fonts that kernel.org is using? But then again aren't there rules that enable a suitable substitute to be found. eg sans or serif, etc?

I can reproduce this with a fresh fedora install USB boot. The problem is intermittent. The problem is transient, a glitch, that can often be remedied by redrawing the page in the framebuffer. As the screenshot picks up the incorrect rendering then, in my opinion there is nothing wrong with the framebuffer memory. This only happens with the this particular video driver. The same problem appears even when running with emulation, ie. making graphics calls from virtio_gpu, but not using virtio_qxl for instance.

Does this still happen if you disable hardware acceleration in Firefox?

• Settings -> General -> Performance
  remove checkmark: [ ] "Use recommended performance settings"
  remove checkmark: [ ] "Use hardware acceleration when available"
• https://support.mozilla.org/en-US/kb/performance-settings

Close and restart Firefox after modifying the setting to apply changes.

• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

If you disable hardware acceleration then the issue doesn't appear (after about 5 minutes). If you enable hardware acceleration then the issue does appear after the first or second page with text.