For Lastpass, I use a Rofi-based frontend on Linux.

A keybinding pops up a search box, I search for the entry I want and paste it into Qutebrowser.

I like that it works outside the browser-- so I can unlock it once and works across all browsers.

Also, I disable autofill anyway. Lastpass has had multiple security issues with their autofill feature in the past and I don't trust it.