Hello,
This behaviour started with the upgrade from debian 10 to debian 11, (regression)
and has gotten worse since,
the graphical interface locks up on frequent base for a long time,
(more than once per hour, locking up from 10minutes to more than a hour, rebooting with a hard reset)
rendering the laptop useless
it might be related to the following bugs:
#990662
#989705
#903426
the errors from dmesg,
* [TTM] Buffer eviction failed
* firmware: failed to load nouveau/nvd9_fuc084 (maybe onrelated?)
a file is attached with more background.
hth,
Wim