diff --git a/src/vector/rageshake.js b/src/vector/rageshake.js
index 0138d6244..249f1f276 100644
--- a/src/vector/rageshake.js
+++ b/src/vector/rageshake.js
@@ -410,8 +410,16 @@ module.exports = {
         }
         logger = new ConsoleLogger();
         logger.monkeyPatch(window.console);
-        if (window.indexedDB) {
-            store = new IndexedDBLogStore(window.indexedDB, logger);
+
+        // just *accessing* indexedDB throws an exception in firefox with
+        // indexeddb disabled.
+        let indexedDB;
+        try {
+            indexedDB = window.indexedDB;
+        } catch(e) {}
+
+        if (indexedDB) {
+            store = new IndexedDBLogStore(indexedDB, logger);
             initPromise = store.connect();
             return initPromise;
         }