Merge pull request #2596 from vector-im/rav/cachebust_version

Add a cachebuster to /version

src/vector/platform/WebPlatform.js

@@ -128,8 +128,18 @@ export default class WebPlatform extends VectorBasePlatform {
 
     _getVersion() {
         const deferred = q.defer();
+
+        // We add a cachebuster to the request to make sure that we know about
+        // the most recent version on the origin server. That might not
+        // actually be the version we'd get on a reload (particularly in the
+        // presence of intermediate caching proxies), but still: we're trying
+        // to tell the user that there is a new version.
         request(
-            { method: "GET", url: "version" },
+            {
+                method: "GET",
+                url: "version",
+                qs: { cachebuster: Date.now() },
+            },
             (err, response, body) => {
                 if (err || response.status < 200 || response.status >= 300) {
                     if (err == null) err = { status: response.status };