Google Chrome has been telling me about a security breach where passwords have been stolen from many websites and it's telling me which of my saved passwords are at risk and that I should change them. That's all good and well, but there are hundreds of them and it would take days of work to change them all manually (or delete the accounts). I made sure to change my passwords for sensitive accounts like ones that have to do with money, etc. but that's not enough for Google.
I've heard that you should always keep passwords secure even if it's a password for an account that a hacker couldn't possibly do anything harmful with. As I understand it, the reasoning behind that idea is that people reuse passwords so getting a password for a harmless account could give someone access to more serious accounts. But that's taken care of already, because all my serious accounts have unique passwords.
If it's okay to leave some unimportant accounts unsecured, is there a way to flag those passwords as "safe" so that Google won't keep bothering me to change the passwords? Alternatively, if there's some reason I haven't thought of that even low-impact accounts need to be secure than is there a way to automate the process of changing the passwords on hundreds of different websites?
Please note that I have been using unique passwords for new accounts for years now. The problem applies to old accounts, which each need to be managed manually. Switching from Google Chrome to a different password manager would not help because the problem is in the compromised accounts and not the password manager.
(Note that I originally asked this on Super User: https://superuser.com/questions/1629437/how-can-i-mitigate-needing-to-change-hundreds-of-google-passwords)