Preferences can't be opened if the extension is installed on read-only file systems

[zoriya]

Hello,

Clicking on the setting's button of the extension, the following error is thrown, since I installed the extension on a read-only file system.

This exception could be prevented by changing the mpris cache to /tmp or the user's XDG_CACHE instead of the extension's location on the file system.

(If you are wondering why the extension is on a read-only file system, this is because my packet manager, nix, place everything on a global read-only file system).

Gio.IOErrorEnum: Error creating directory /etc/profiles/per-user/zoriya/share/gnome-shell/extensions/widgets@aylur/media/mpris-cache: Read-only file system

Stack trace:
  _cacheSize@/etc/profiles/per-user/zoriya/share/gnome-shell/extensions/widgets@aylur/pref/pages.js:364:17
  _init@/etc/profiles/per-user/zoriya/share/gnome-shell/extensions/widgets@aylur/pref/pages.js:345:14
  SubPage@/etc/profiles/per-user/zoriya/share/gnome-shell/extensions/widgets@aylur/pref/pages.js:17:1
  MediaPlayerPage@/etc/profiles/per-user/zoriya/share/gnome-shell/extensions/widgets@aylur/pref/pages.js:316:1
  _init@/etc/profiles/per-user/zoriya/share/gnome-shell/extensions/widgets@aylur/prefs.js:120:33
  MainPage@/etc/profiles/per-user/zoriya/share/gnome-shell/extensions/widgets@aylur/prefs.js:102:1
  fillPreferencesWindow@/etc/profiles/per-user/zoriya/share/gnome-shell/extensions/widgets@aylur/prefs.js:129:16
  _init@resource:///org/gnome/Shell/Extensions/js/extensionPrefsDialog.js:27:29
  ExtensionPrefsDialog@resource:///org/gnome/Shell/Extensions/js/extensionPrefsDialog.js:10:4
  OpenExtensionPrefsAsync@resource:///org/gnome/Shell/Extensions/js/extensionsService.js:124:33
  async*_handleMethodCall@resource:///org/gnome/gjs/modules/core/overrides/Gio.js:373:35
  _wrapJSObject/<@resource:///org/gnome/gjs/modules/core/overrides/Gio.js:408:34
  run@resource:///org/gnome/Shell/Extensions/js/dbusService.js:186:20
  main@resource:///org/gnome/Shell/Extensions/js/main.js:22:13
  run@resource:///org/gnome/gjs/modules/script/package.js:206:19
  start@resource:///org/gnome/gjs/modules/script/package.js:190:8
  @/nix/store/yr176vsj2glj4ll0ap10d0fkwb7lcp7a-gnome-shell-44.1/share/gnome-shell/.org.gnome.Shell.Extensions-wrapped:7:17

If you want, I can open a PR to fix this, running a quick search holds only 3 lines to update.

[Aylur]

Had a quick look and yes, it is just a few lines to fix this. I am a bit busy right now, and I want to do some other things too before pushing another version but I am on it.

[4JX]

@Aylur the commit does not fully work as the parent aylur/ folder does not exist, see 4JX@f291689 for a fix