Dashlane, LastPass, and KeePass: Research carried out by Independent Security Evaluators (ISE) uncovered that while running in the background, these password managers could leak unencrypted credentials. According to the researchers, these companies don’t always encrypt and clear passwords from the computer’s memory when the user logs out."
"2015
KeePass: When this program runs on a computer where a logged in user has the KeePass database unlocked, KeeFarce (a hacking tool) decrypts the entire database and writes it to a file that the hacker can easily access. In theory this kind of hack makes all password managers vulnerable."
I don't use Password Managers at all, and wouldn't really recommend others to do so either. You have to trust a lot more stuff than just yourself. The company behind it, the encryption, the cloud storage, etc. https://password-managers.bestreviews.net/faq/which-password-managers-have-been-hacked/
As for LastPass, it worked in 2022 (https://forum.palemoon.org/viewtopic.php?f=46&t=28758&p=232592#p231532) & (https://forum.palemoon.org/viewtopic.php?f=46&t=28758&p=232592#p231564)
Don't use closed-source, web/cloud based password managers.
https://keepass.info/
From my link above:
"2019
"2015
Same when you copy a password into the clipboard, it's cleartext.