Comment # 7 on bug 1140198 from Marguerite Su

some briefings here:

Wayland can load environment variables from
/etc/environment and .pam_environment

But that���s not enough.

1. Fcitx and IBus can���t write into one same file.
2. With both installed, you may have two INPUT_METHOD set even if
/etc/environment.d is usable 
3. Packagers can not touch user home directory, because no way to clean the
configurations at uninstall

@ftake implemented chameleon-tongue acting like an ���inputmethodd���
to detect, sort and set env in one application, but that���s 
still not enough, because other applications may use
/etc/environment too