diff --git a/org.kde.Sdk.json b/org.kde.Sdk.json
--- a/org.kde.Sdk.json
+++ b/org.kde.Sdk.json
@@ -15,6 +15,8 @@
         "org.freedesktop.Platform.Icontheme",
         "org.freedesktop.Sdk.Extension",
         "org.freedesktop.Platform.VAAPI.Intel"
+        "org.freedesktop.Platform.ffmpeg",
+        "org.gtk.Gtk3theme"
     ],
     "add-extensions": {
         "org.kde.Sdk.Docs" : {