For people who want to experiment with LEMONADE-style IMAP servers, I created a little developers guide to installing one that supports the IDLE and CONDSTORE capabilities. You can also try M-Box or others. It’s a wiki, so people are allowed to improve the guide.
This doesn’t mean that I already have support for these two capabilities covered in tinymail. It does mean, however, that I’m preparing my test environment. A software developer usually prepares a test environment for a reason. That reason is, indeed, that I’m on it (implementing support for lemonade imap features in tinymail).
It will be developed piece by piece. I definitely have other todo items and priorities too. Since only a few running IMAP servers support this already (and by running I mean IMAP servers that are actually running, not just an software version of an IMAP server, but an active and working deployment at a site), unless you install your own, it’s not yet extremely important. However, I do agree, fully, that the lemonade proposals and drafts are absolutely interesting and are probably going to be very important for the mobile world (that includes laptop users on shitty wireless networks).