Do both computers use the same Chrome versions & preferences? This is a security warning of Chrome, not one of macOS and therefore system preferences do not matter in this case.
thanks for giving me a hint to go and look in the right spot, for some reason I thought it was a Catalina security setting, but it really is a Chrome issue.
I found some links pointing to this piece of doc:
and the issue surfaced sometimes in the last few months, and maybe I had not used this feature on the second machine so I did not notice until today. Still, I don’t have the issue on the other, so go figure!
The fix is a simple terminal command changing a default policy:
defaults write com.google.Chrome ExternalProtocolDialogShowAlwaysOpenCheckbox -bool true
and after restarting Chrome, now we will see the checkmark on the page so that the new default will be remembered, like so:
This Reddit discussion gave me some clues
https://www.reddit.com/r/chrome/comments/d3v4yr/dont_ask_again_checkbox_on_popups_not_available/
then I found the corresponding bug:
https://bugs.chromium.org/p/chromium/issues/detail?id=982341
and this discussion on SuperUser provided the answer:
and now the issue is fixed.
It would be nice to understand why I don’t have the issue on the other Chrome installation, same OS and same Chrome version, but I think I will pass and just enjoy the result!
Thanks and bye, Luca