The browser's feature was what I meant - it seems to be somehow disabled in roundcube, since with every computer we try, with either MSIE6 or Firefox 1 or 2, the browsers don't give us the popup. But they do it for every other username/password form we try.
So if there is not a setting for it, the reason has to be either the login technique roundcube uses (but my friend has told me that in their ancient installation it works - perhaps the technique has been changed at some point?), or my installation is somehow screwed up - but the cookies/sessions seem to be working ok otherwise.
Strange. Can someone confirm that roundcube (0.1-rc1.1) either:
a) does give them the browser's "remember username and password" window just like with other login forms
or
b) doesn't give the window, even if it does with other login forms.
Answer
b would mean there is nothing I can do about this (except tweaking roundcube's login quite a lot, if I can), but if the answer is
a, there's still something for me to work with