Improving theme support for GTK 2 apps

https://forum.snapcraft.io/t/improving-theme-support-for-gtk-2-apps/7693

installer/snap/snapcraft.yaml

@@ -7,7 +7,6 @@ confinement: strict
 grade: stable
 
 architectures: [amd64]
-base: core18
 
 apps:
   filebot:
@@ -24,10 +23,24 @@ apps:
       - network
       - network-bind
 
+plugs:
+  gtk-2-engines:
+    interface: content
+    target: $SNAP/lib/gtk-2.0
+    default-provider: gtk2-common-themes:gtk-2-engines
+  gtk-2-themes:
+    interface: content
+    target: $SNAP/share/themes
+    default-provider: gtk2-common-themes:gtk-2-themes
+  icon-themes:
+    interface: content
+    target: $SNAP/share/icons
+    default-provider: gtk-common-themes:icon-themes
+
 environment:
-  GTK_PATH: $SNAP/usr/lib/x86_64-linux-gnu/gtk-2.0
-  GTK_DATA_PREFIX: $SNAP/usr
-  XDG_DATA_DIRS: $SNAP/usr/share:$XDG_DATA_DIRS
+  GTK_PATH: $SNAP/lib/gtk-2.0
+  GTK_DATA_PREFIX: $SNAP
+  XDG_DATA_DIRS: $SNAP/share:$XDG_DATA_DIRS
 
 parts:
   filebot:
@@ -40,16 +53,10 @@ parts:
     stage-packages:
       - openjdk-8-jre
       - openjfx
-      - mediainfo
+      - libmediainfo0v5
       - libchromaprint-tools
       - p7zip-full
       - p7zip-rar
       - xdg-utils
-      - curl
-      - libgnome-2-0
-      - libgnomevfs2-0
-      - gtk2-engines-murrine
-      - libcanberra-gtk-module
-      - hicolor-icon-theme
     after:
       - desktop-gtk2