Well, I'll go directly to the point, Adding servers to favorites does NOT work, at least for me.

I simply click on the server once, click the "Add to favorites" button, check the "Favorites" tab, and there's nothing. Tested with ANY server, still does not work. May fix this in next update? Or may you help me (maybe it's only my own error)?

No, this is not implented, yet atleast. So it isn't a bug.

Favorites and history tab don't work as of now. They may be fixed in upcoming revisions.