My question is: has anyone successfully got cut/paste working over x2x between two Ubuntu PCs? Is it possible? As I can't find any documentation/examples only a few references in articles saying it should/could/might work.

If it's not possible I would like to know if it's actually possible by other means (Barrier? Synergy?).

I already use x2x to control a Ubuntu 20.10 PC with my main PC's keyboard mouse (also Ubuntu 20.10) and it works great, but no cut/paste.

I read a few articles which say that if you start x2x using an alternative method (this needs some tweaks like xhost and other config to have tcp port 6000 listening) then cut/paste should work but although I can get x2x working with either method I have had no luck getting any sort of cut/paste working.

e.g. forwarding method:

ssh -X remote_machinename_or_ip_address x2x -direction_of_the_remote_display -to :0

and second alternative method:

x2x -to IP_or_hostname:0.0 -direction_of_the_remote_display