Problems with IBus that I've only experienced on Trisquel

Hello, I've been meaning to ask about this for a long time, but haven't gotten around to it yet.

I've been using IBus for a long time for Japanese input. I've used it on Fedora and Linux Mint in the past with no problems. But for some reason, IBus doesn't work correctly at all on Trisquel.

When Anthy (the usual Japanese input method) is on, I can type hiragana, but that's it. Normally, IBus allows you, after typing hiragana, to turn the hiragana into kanji and/or katakana by pressing the space bar (this is a common feature for Japanese input methods in general, and necessary for typing effectively in Japanese). However, this doesn't seem to work on Trisquel. I have no idea why this would be; there is no setting for which key should convert to kanji that I'm aware of, and if this was the problem, I would expect IBus to also misbehave on Linux Mint, which uses the same home directory as Trisquel if I run it (it doesn't; it behaves normally).

Another, more minor problem is there are some fields where IBus should work, but doesn't (at all; not even hiragana entry). The only one I know of is gedit's main field.

Has anyone else witnissed or heard of this with IBus?