Many/most password managers do TOTP in their browser extensions already - at least on paid tiers. (Bitwarden, Lastpass for sure).

It's the only way a team can effectively use TOTP, which still offers a lot of protection.

If you have any concern I would gladly hear technical insight about the threat model involved. The cross-post on the Privacy communities sparked more conversation if you want to follow up on that point : https://lemmy.ml/post/12744864.

Extension "authenticator" has been around for more than a decade now. I am sharing something that is small, simple, auditable and secure (no permission to do anything but past on clipboard).

If the thread model involve physical device access, then yes. However, consider that the attacker might not have access to the device with this 2FA.