Software not using Dolphin open/save file picker

Some programs use gtk file picker rather than calling the KDE/Dolphin file picker.

A subset of these programs will use gtk portals automatically, which results in the gtk file picker being replaced with the KDE picker.

Some support it but won't use it automatically, and it has to be forced with the following env vars:

sudo vim /etc/environment

GTK_USE_PORTAL=1
GTK_DEBUG=portals
XDG_CURRENT_DESKTOP=KDE

For other software, it's necessary to install the rpm, because these don't use portals and instead directly call the desktop environment's window methods, which hasn't been included in the flatpak. This impacts libreoffice and possibly others.

For yet other programs (e.g. audacity and filezilla) they still display the gtk file dialog even when installing the rpm. Most likely these programs don't support using portals for the file picker and also don't support the desktop environment directly either. I have no solution for these yet.