Hi,
I am not the maintainer of this package but came to this bug after hearing it on a Debian JP workshop session.
I think what should happen is the following:
For now, Endless OS should create its customization package which used dpkg-divert to disable ibus-mozc's autostart script and provides its own per-user input method setting script (or use gnome-initial-setup?). After all, the act of installing all the language support packages is a non-typical use case.
Here is my rationale and comment for the future direction.:
Fundamental problem is that Debian Package installation script can configure system wide settings via post-inst script but not each user's personal settings. Since ibus input method activation is performed per-user basis, we need some mechanism to make 99% of use case as smooth as possible like what is done. Under normal use case, whoever install ibus-mozc expects it to work upon first login to the system.
I do understand what ibus-mozc is doing may not be the best technical solution but is a reasonable **DE independent solution**.
If you can come up with a new **DE independent** per-user IM setting package and upload to Debian, we can stop using current mechanism. That will be great contribution to Debian from Endless OS. (FYI: I like your Gnome DE mod code which I use via extension.)
Please remember Debian need to support many DEs.
Best regards,
Osamu