There is no such section on upgrades from OH2 to OH4.
Show the link.
All the quotes the others have given here are from the official openHABian docs or openHABian section of the Release Notes.
NONE of those did nor will ever tell to use apt at all yourself.
OpenHABian is a menu driven system it’s made that you don’t have to use apt.
Anything else is just a (false) interpretation of yours.
No. THE official openHABian docs definitely do NOT mention Ubuntu other than with the clear statement that it is NOT supported. It never ever was.
Reading and respecting the (right) docs rather than making assumptions would have.
I have the feeling you have either a fundamental misunderstanding of what openHABian is versus what openHAB itself is, or you have been using some wrong docs or misreading the right ones.
Rather than just refer to those please give the exact links here.
I’ll adjust the thread title and solution tick, too, as they’re misleading to readers.
Next time please also mind the posting rules below and clarify right in the original post what system you are using and what’s the proper context required for any reader to apply to understand your post.
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