Sorry for the delay.
(I hope it's the last, I use elpaca).
No, the behavior is not actually the same: for me (hoping my configuration doesn't interfere), everything goes “as expected”, except that the second capture cancels the first.
In other words, I can insert, in the title of the first one (using org-roam-node-insert):
[[id:idOfTheSecondCaptureAlreadyDid][aDescription, the second capture]]
BUT, when I finish the first one, I get the error:
Error running timer 'org-capture': (error “Capture abort: Selecting deleted buffer”).
So you can't stack captures?
Thanks again for your future answers.