Excerpts from Davide Spanu's message of 2019-11-10 09:58:08 +0100:

I have a problem with my koha server. I realized that after importing a record (so before entering the copy data) the window of some browsers closes automatically (Chrome and Firefox). Before this problem did not occur (and I did not change any settings in either Koha or the server). Can you tell me what it can depend on?

This is a known bug: https://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=23680 I manually applied the patch shown in comment 7 and that fixed the problem.