danny1961

Sure enough, I’ve tried a standard theme and no plugins.

This is the closest topic https://en.forums.wordpress.com/topic/problem-with-scheduled-posts but it offers no specifics as to the solution.

Me, too. The bug is random: I have three blogs with 2.1.3. Two blogs work ok, one blog (one the same site!) doesn’t add categories or comments.
Tried various browsers; Linux server.

There is one difference, however: when I’m trying to close add categories page, it gives a warning “do you want to navigate away from this page?” Working blogs show no such warning.

Have no problem at all using gz with Kubrick theme and several plugins. Much faster, as a matter of fact.

Just tried to install another blog with English content and tiga theme, still gz doesn’t work.
So the bug seems to be that the theme do not support the second blog on the same domain compressed with gzip.
Curiously, compression works only with the FIRST blog installed (and running tiga). For example, gz works on the first blog, but not second and third. But not on the second, even if I turn off the compression on the other two blogs.
Settings on all three blogs are exactly the same.