Is there privacy feature?
For sure. It's forked from Monero, so, it includes every privacy feature Monero has implemented so far.
1) Which wallet are you using? CLI or GUI? What's triggering the unresponsiveness?
2) Those are just minor changes, small fixes, none critical, which will all be incorporated in the next release, 3.0. Until then, 2.8.1 is still fine. But fell free to use 2.8.2 if you desire.
1) GUI
for example - start, sync, wait an hour, click to History => "Not Responding" occur
2) It's a good idea to put an anouncment about any changes of wallet application (just for security reasons).
1) Very strange. As far as I know nobody ever reported such problem. Seems to be an isolated case. Anyway, seems like you're running a llocal node, correct? Could you try to use a remote one, just for testing purposes? Try also just running the daemon (and without the GUI wallet open).
2) Don't worry, we always announce all the big updates. That one, specifically, wasn't exactly announced because it was just a minor fix, nothing critical or important.