I have noticed that when I type in some programs, Text Editor, Terminal, Bluefish, Gnome Baker, etc. the mouse cursor disappears while I am typing. In other programs like Firefox and LibreOffice, it does not.

I am not an application programmer, but I imagined it has to do with their cross-platform nature and the way they are compiled or the toolkits they use. Then I noticed that Gnome-Do behaves the same way, the cursor stays on screen while typing.

Why is there inconsistent handling of the mouse cursor, while typing, across different applications?

Thank you.