Partial merge of develop to experimental

Does not include #2336 as the file has been moved out from underneath it:
will do this separately

src/settings/Settings.js

@@ -151,6 +151,11 @@ export const SETTINGS = {
         displayName: _td('Always show encryption icons'),
         default: true,
     },
+    "showRoomRecoveryReminder": {
+        supportedLevels: LEVELS_ACCOUNT_SETTINGS,
+        displayName: _td('Show a reminder to enable Secure Message Recovery in encrypted rooms'),
+        default: true,
+    },
     "enableSyntaxHighlightLanguageDetection": {
         supportedLevels: LEVELS_ACCOUNT_SETTINGS,
         displayName: _td('Enable automatic language detection for syntax highlighting'),