Cannot reveal passwords in Password History with Option key

Hey there jinux_go

Yes, this is expected behaviour. Holding ⌥ Option on the keyboard should never expose more than one password, even if they're "only" previously-used ones, so you'll need to click Reveal from the 🔽 down-arrow menu, like this:

If you want to show all passwords, in all fields, all the time, you can turn this on in the Security tab of Preferences:

Please let me know if you have any questions, or would like any further help. :)

— Grey