When visiting a site with an invalid SSL certificate, Chrome displays an alert which says:
Your connection is not private
But it is still possible to proceed to the site by clicking "Advanced > Proceed to example.org (unsafe)", after which Chrome remembers the exception for this site (tested in Google Chrome Version 79.0.3945.117) for future sessions.
Now, it is possible to remove the exception for the current site by clicking the "Re-enable warnings" link from the address bar "Not secure" badge where a message like the following appears:
You have choosen to disable security warnings for this site. Re-enable warnings
But is it possible to "Re-enable warnings" for all sites, not only for the current one?.