Some applications don't like IBUS + m17n, and certain input mim files. For example, LibreOffice and JabRef. Trying to type "ācārya" will give the result is "ācāry a". And in other strings, some letters are inverted: "is" becomes "si" and so forth.
Here's the fix.
Create a file called, say ibus-setting.sh with the following one-line content:
export IBUS_ENABLE_SYNC_MODE=0Copy the file ibus-setting.sh to the directory /etc/profile.d/, like this:
sudo cp ibus-setting.sh /etc/profile.dMake the file executable, like this:
sudo chmod +x /etc/profile.d/ibus-setting.shLogout and login again.
This fixes the behaviour of IBUS + m17n with most applications, including LibreOffice and Java applications like JabRef. However, some applications compiled with QT5 still have problems. So, for example, you have to use the version of TeXStudio that is compiled with QT4, not QT5. [Update September 2018: QT5 now works fine with Ibus, so one can use the QT5 version of TeXstudio with no problem.]