Hi guys
I have a similar problem and also lack the understanding to put this rewrite rule in place.

I need to only remove these characters from any URL on our website.
?rid=

from this:
HTML Code:
https://rpmdigital.co.uk/coffee/?rid=A611F4
to this:
HTML Code:
https://rpmdigital.co.uk/coffee/A611F4
We have pages generated for specific users giving them a unique ID which is permanent and added to the end of every page that they visit. Ideally we would like to hide ?rid= within the URL whenever it occurs.

Really appreciate some help on this

Kind Regards
Matt