When using the official Runelite Linux AppImage it is impossible to use the --configure
flag on the AppImage, at least in my case on Fedora 37.
When saving the configure dialog a stack trace happens with the following error
java.nio.file.FileSystemException: /tmp/.mount_RuneLic9UypO/settings.json: Read-only file system
To get around this you can run ./RuneLite.AppImage --appimage-extract
and this will extract the AppImage into the local directory.
Then to run Runelite simple use the following ./squashfs-root/RuneLite
.