Merge branch 'develop' of https://github.com/matrix-org/matrix-react-sdk into rxl881/snapshot

src/ScalarMessaging.js

@@ -602,8 +602,16 @@ const onMessage = function(event) {
     //
     // All strings start with the empty string, so for sanity return if the length
     // of the event origin is 0.
+    //
+    // TODO -- Scalar postMessage API should be namespaced with event.data.api field
+    // Fix following "if" statement to respond only to specific API messages.
     const url = SdkConfig.get().integrations_ui_url;
-    if (event.origin.length === 0 || !url.startsWith(event.origin) || !event.data.action) {
+    if (
+        event.origin.length === 0 ||
+        !url.startsWith(event.origin + '/') ||
+        !event.data.action ||
+        event.data.api // Ignore messages with specific API set
+    ) {
         return; // don't log this - debugging APIs like to spam postMessage which floods the log otherwise
     }