you're right, the gap isn't that big. Hard to put my finger on it, but for me the general look&feel and 'snappines' of the interface still feels not as refined as gmail.
The threaded view is not nearly as good as gmail's where you just scroll to see the next message (once you view a single message). It feels like there's lots more double-clicks going on in roundcube to get to view messages and interact with things...
I suppose these are not huge functionality gaps, more refinements to the UI. Functionality-wise it would be nice to have some intelligent filters in roundcube like google's. That's where gmail is a combination of an email client and server though.
For filters I use Sieve [1] (comes with Cyrus Imap and I believe some others like Dovecot). There are a few plugins for roundcube that provide an interface for managing sieve rules [2], [3]. I tested both linked below and both worked, but they seem geared toward users who want a UI for rule creation, like in Gmail, whereas I have an existing sieve script I want to edit directly. Anyway, filter functionality is there in roundcube that's at least comparable to gmail, so long as your imap server supports sieve.
The threaded view is not nearly as good as gmail's where you just scroll to see the next message (once you view a single message). It feels like there's lots more double-clicks going on in roundcube to get to view messages and interact with things...
I suppose these are not huge functionality gaps, more refinements to the UI. Functionality-wise it would be nice to have some intelligent filters in roundcube like google's. That's where gmail is a combination of an email client and server though.