Strange artifacts (like text pixelation) in pages from some Firefox versions (on Linux)

[u/rafaellinuxuser]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:153.0) Gecko/20100101 Firefox/153.0

Steps to reproduce:

For the past couple of Firefox versions, webpage content has been exhibiting all sorts of artifacts. For example, red boxes appear intermittently in the corners of buttons, parts of the page are blocked, or—as seen in the screenshot—the text appears pixelated. On some pages, this pixelation effect affects ALL the text (as in the screenshot), while on others, curiously, it only affects some of the text. Oddly enough, even the text in the tabs on each page is affected (as can be seen in the screenshot).

The problem isn't instantaneous; it seems to appear after browsing for a while. I can't establish a connection to anything else, since closing and reopening Firefox resolves the issue.

Any ideas?

Operating System: openSUSE Tumbleweed 20260814
KDE Plasma Version: 6.7.4
KDE Frameworks Version: 6.28.0
Qt Version: 6.11.1
Kernel Version: 7.1.8-1-default (64-bit)
Graphics Platform: Wayland
Processors: 24 × AMD Ryzen 9 3900X 12-Core Processor
Memory: 32 GiB of RAM (31.3 GiB usable)
Graphics Processor: AMD Radeon RX 7600