Steps to reproduce: Login a site which uses JavaScript to submit login info, e.g. https://vnet.one/login (this is a Chinese website. I've registered a test account, and if anyone wants to test it, I can send the username and password privately) Expected result: There should be a "key" icon on the left of the location bar, and a saving login info prompt should be shown. Actual result: No "key" icon on the left of the location bar, and no prompt is shown. It seems Chrome and Safari is able to detect this kind of login form and ask user to save password. Safari has a probably better experience that they add an icon inside the password field so that user can always save password when you want, rather than need of waiting for the browser's prompt.

It could also be due to that there is no <form> element at all.

If there is no <form> at all then bug 1166947 should fix this. Please confirm using the patches on the bug or when it lands.

Xidorn, can you confirm this is now fixed? If not, please attach debug logs: https://wiki.mozilla.org/Firefox:Password_Manager_Debugging

Yes, it is fixed now. So I suppose this should be a duplicate of bug 1166947.