What is fusion here?

Multiling-o keyboard might fit the bill.

There is this other line of thinking. Most frequently used should be more easily accessible hence bigger. That is what is causing confusion here.

Ah, that would be bliss.

I thought at least open source ones would do it otherwise considering the freedom they represent.

Looks like it has not reached that point yet.

Suppose I want to keep a backup and decide later what I want to discard, I will have to keep on doing it manually each time to update the archive.

WhatsApp did it properly before where I could easily backup the whole directory which included all media and chat database locally. But now they are forcing Google backups which I do not like. I was looking for alternatives but they all seem to need this kind of manual saves. Eg. Signal, Twin Me, and the recently tried Jami.