Comment # 6 on bug 1216517 from Eric van Blokland

I have experienced this issue for a couple of months but have been too busy to
file a report.

In my case the problem started after a kernel update. The last kernel version
where plymouth works reliably for me is 6.5.3-1. It broke with 6.5.4-x.

Since that kernel version my system takes more than 10 seconds, up from about 2
seconds before, to initialize devices (usb, graphics, disks). 

When plymouth is started my graphics card does not become available in time and
plymouth falls back to text mode. (framebuffer device, with the little blocks)

To check if this is your issue as well, search your logs for the line "[drm]
Initialized amdgpu". Tumbleweed has a timeout of 8 seconds in
/etc/plymouth/plymouthd.conf.

My hardware:

AMD Ryzen 2700x
AMD Radeon 6800XT
X470 Chipset