Can you accept/reject meeting invites with it? The Tbsync extension that I am using does not have this feature.
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I noticed I'm running it with "java -Xmx512M" which probably explains the half-GB of ram usage. It's possible that if I increased that value it would perform better with large folders, but I keep my inbox fairly reasonable and I don't care if the other folders take a bit of time to sync.
Also, FWIW, it's the 10th largest item in my top listing, with even Thunderbird using more RAM (850MB). I suspect mutt, offlineimap and davmail would combine to be smaller than TB alone.
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Also consider getting your employer to buy you more RAM? A 32GB SO-DIMM kit from corsair is under $200, so nobody should have to worry about half a gig on their work machine...
Then I can use whichever client I like. Otherwise it's just bouncing between which client has had the exchange plugins updated most recently.
As a bonus, it's distributed as a jar, so you can download and run for the latest support, even on an LTS of a Linux distro