A day or two ago I upgraded my already beowulf system -- just the
routine upgrade to keep it up-to-date.

Not I suddenly have trouble using copy and paste.

I know there are multiple conventions for this, with each piece of
software doing its own thing. But it was usually possible to try
different combinations and after a few tries get something copied.

No longer. Sometimes it works and sometimes it doesn't and nothing
seems to help.

I haven't even been able to copy-paste from a qterminal with mutt
running in it to the *same* qterminal with the same mutt process
running in it (copying an email address from one messate to the headers
of another).

And no luck copying a URL in one browser (running elsewhere but
displaying locally using X) into another browser (running locally).

Sometimes it does manage to copy and paste, but it pastes the wrong
thing, presumably from a different copy buffer. Or an older entry rom
what ought to be the same copy biffer.

Does anyone know what has changed? I'm using lxqt. Techniques that
have worked for years with a bit of friction have suddenly stopped
working altogether.

-- hendrik