2FA is not returning codes when settings has "clear history and site data when Firefox closes" is checked in settings in 152.0.4 version.

I'm not sure what the relation is between 2FA not returning codes and the "clear history and site data" preference being checked. They don't affect each other. Could you please elaborate? Are you implying that when the preference is not checked, the 2FA successfully returns codes?

Da!!!!, Yes, it allows 2FA codes when unchecked. 2FA codes are using the same area that is being cleared when the switch is checked.

Which "2FA"? (certain TOTP provider? or an authenticator app? or TXT messages from individual sites?)

Do you have an example of an account provider and a service to sign into you're having trouble with? And if the answer is "all", could you provide some popular option from those you can't sign into? Thanks.

This is about 2FA codes when you use Firefox, obviously, and say a Bank, or online store like Amazon. Logging in to those sites never respond when you ask for a code during login. There is just no response. So, it appears that the storage is being used to return a code, it has too, is being cleared and causing the site to never return the code. Uncheck the setting in Firefox and codes are returned just fine. You have to restart Firefox, each time you check or uncheck the setting.

I'm sorry I'm still not following. Firefox doesn't store any multi–factor credentials for your sites, and neither receives any of these codes, so there is no "storage" for these. How are you receiving them? Via email? Or via mobile text message? Or you mean different multi–factor authentication flow?

If what you're describing effectively is that when you're cleaning out site data on exit and they don't provide you any form response on the first visit, you might need to get in touch with these site operators as to why you're not getting the response.

Have you tried a) Private Window to eliminate any session data, and b) restarting into Troubleshoot Mode (from Help menu) to eliminate any "privacy" addons interfering with the session data of said sites?