How can I make a specific user's posts uneditable/undeletable?

[David Lama]

i know i can make a account unchangable. but what about doing that to that accounts posts/threads? is it possible? if so how?

im basically asking for what this user asked for

https://vborg.vbsupport.ru/showthread.php?t=105190&highlight=posts+uneditable

can anyone please help?