[HEADS UP] Update your Qt application with access to KDE/Gnome configuration

[Jan Grulich]

Hi everyone.

there were some changes in flatpak back then, disabling inheritance of 
permissions from runtime to applications using it. We used to allow read 
access to kdeglobals configuration file in KDE runtime, where applications can 
read system color, font, icons and so on. This doesn't work anymore and this 
access needs to be set per application. 

All you need to do is to add following into finish-args in your manifest:
"--filesystem=xdg-config/kdeglobals:ro"

Similar approach will most likely be needed for Gnome, to allow QGnomePlatform 
access dconf configuration, this can be achieved with following finish-args:
"--env=DCONF_USER_CONFIG_DIR=.config/dconf"
"--filesystem=xdg-run/dconf"
"--filesystem=~/.config/dconf:ro"

I opened PRs for all KDE applications in flathub, adding access to kdeglobals, 
but it's not in my manpower to go through all Qt apps and open dozens of PRs 
myself, when it's easier for maintainers to simply do the change without 
forking repositories.

Thank you.

Regards,
Jan