Autofill problems

I’m getting a variety of results with autofill depending on the website.
About 1/2 (of 50+) work OK.
For some I have go to the BitWarden icon and click the site name. Then it autofills. BitWarden knows it’s on the site because the site shows up under the BitWarden icon. It just doesn’t autofill.
There’s one site that doesn’t autofill unless I click the sitename twice. This is a bank website which I understand can be pretty nasty, login-wise.
One site with username and password on separate pages doesn’t autofill unless I go to the BitWarden icon. The site is there and if I click it BitWarden autofills both pages. This is also a bank website.

Are these just “mac quirks” and I have to live with them or am I doing something wrong?

LastPass had an area of their forum set up specifically for troublesome websites. Maybe a 3rd item along with user-to-user and feature requests? It was very helpful to have all of this type problems together.

Thanks in advance
Macbook Po
Mojave v10.14.6
Safari v10.0.3