diff --git a/src/crypto/algorithms/megolm.js b/src/crypto/algorithms/megolm.js
index af311e16b..d1115f00e 100644
--- a/src/crypto/algorithms/megolm.js
+++ b/src/crypto/algorithms/megolm.js
@@ -264,8 +264,8 @@ MegolmEncryption.prototype._prepareNewSession = async function() {
     );
 
     if (this._crypto.backupInfo) {
-        // Not strictly necessary to wait for this
-        await this._crypto.backupGroupSession(
+        // don't wait for it to complete
+        this._crypto.backupGroupSession(
             this._roomId, this._olmDevice.deviceCurve25519Key, [],
             sessionId, key.key,
         );
@@ -849,7 +849,8 @@ MegolmDecryption.prototype.onRoomKeyEvent = function(event) {
         this._retryDecryption(senderKey, sessionId);
     }).then(() => {
         if (this._crypto.backupInfo) {
-            return this._crypto.backupGroupSession(
+            // don't wait for it to complete
+            this._crypto.backupGroupSession(
                 content.room_id, senderKey, forwardingKeyChain,
                 content.session_id, content.session_key, keysClaimed,
                 exportFormat,
@@ -972,6 +973,18 @@ MegolmDecryption.prototype.importRoomKey = function(session) {
         session.sender_claimed_keys,
         true,
     ).then(() => {
+        if (this._crypto.backupInfo) {
+            // don't wait for it to complete
+            this._crypto.backupGroupSession(
+                session.room_id,
+                session.sender_key,
+                session.forwarding_curve25519_key_chain,
+                session.session_id,
+                session.session_key,
+                session.sender_claimed_keys,
+                true,
+            );
+        }
         // have another go at decrypting events sent with this session.
         this._retryDecryption(session.sender_key, session.session_id);
     });
diff --git a/src/crypto/index.js b/src/crypto/index.js
index d45caabe3..20341c4b2 100644
--- a/src/crypto/index.js
+++ b/src/crypto/index.js
@@ -1061,7 +1061,7 @@ Crypto.prototype.backupGroupSession = async function(
         sessionId: sessionId,
     }]);
 
-    this._maybeSendKeyBackup();
+    await this._maybeSendKeyBackup();
 };
 
 Crypto.prototype.backupAllGroupSessions = async function(version) {
@@ -1077,7 +1077,7 @@ Crypto.prototype.backupAllGroupSessions = async function(version) {
         },
     );
 
-    this._maybeSendKeyBackup();
+    await this._maybeSendKeyBackup();
 };
 
 /* eslint-disable valid-jsdoc */    //https://github.com/eslint/eslint/issues/7307
diff --git a/src/crypto/store/indexeddb-crypto-store-backend.js b/src/crypto/store/indexeddb-crypto-store-backend.js
index d0bb9f1b7..d5b66c30f 100644
--- a/src/crypto/store/indexeddb-crypto-store-backend.js
+++ b/src/crypto/store/indexeddb-crypto-store-backend.js
@@ -501,7 +501,6 @@ export class Backend {
         const objectStore = txn.objectStore("sessions_needing_backup");
         return Promise.all(sessions.map((session) => {
             return new Promise((resolve, reject) => {
-                console.log(session);
                 const req = objectStore.delete([session.senderKey, session.sessionId]);
                 req.onsuccess = resolve;
                 req.onerror = reject;
diff --git a/src/crypto/store/localStorage-crypto-store.js b/src/crypto/store/localStorage-crypto-store.js
index 71a904fd8..cad6a7d64 100644
--- a/src/crypto/store/localStorage-crypto-store.js
+++ b/src/crypto/store/localStorage-crypto-store.js
@@ -167,43 +167,52 @@ export default class LocalStorageCryptoStore extends MemoryCryptoStore {
     }
 
     getSessionsNeedingBackup(limit) {
+        const sessionsNeedingBackup
+              = getJsonItem(this.store, KEY_SESSIONS_NEEDING_BACKUP) || {};
         const sessions = [];
 
-        for (const session in getJsonItem(this.store, KEY_SESSIONS_NEEDING_BACKUP)) {
-            const senderKey = session.substr(0, 43);
-            const sessionId = session.substr(44);
-            getEndToEndInboundGroupSession(senderKey, sessionId, null, (sessionData) => {
-                sessions.push({
-                    senderKey: senderKey,
-                    sessionId: sessionId,
-                    sessionData: sessionData,
-                });
-            })
-            if (limit && session.length >= limit) {
-                break;
+        for (const session in sessionsNeedingBackup) {
+            if (Object.prototype.hasOwnProperty.call(sessionsNeedingBackup, session)) {
+                const senderKey = session.substr(0, 43);
+                const sessionId = session.substr(44);
+                this.getEndToEndInboundGroupSession(
+                    senderKey, sessionId, null,
+                    (sessionData) => {
+                        sessions.push({
+                            senderKey: senderKey,
+                            sessionId: sessionId,
+                            sessionData: sessionData,
+                        });
+                    },
+                );
+                if (limit && session.length >= limit) {
+                    break;
+                }
             }
         }
         return Promise.resolve(sessions);
     }
 
     unmarkSessionsNeedingBackup(sessions) {
-        const sessionsNeedingBackup = getJsonItem(this.store, KEY_SESSIONS_NEEDING_BACKUP) || {};
-        for(const session of sessions) {
+        const sessionsNeedingBackup
+              = getJsonItem(this.store, KEY_SESSIONS_NEEDING_BACKUP) || {};
+        for (const session of sessions) {
             delete sessionsNeedingBackup[session.senderKey + '/' + session.sessionId];
         }
         setJsonItem(
-            this.store, KEY_SESSION_NEEDING_BACKUP, sessionsNeedinBackup,
+            this.store, KEY_SESSIONS_NEEDING_BACKUP, sessionsNeedingBackup,
         );
         return Promise.resolve();
     }
 
     markSessionsNeedingBackup(sessions) {
-        const sessionsNeedingBackup = getJsonItem(this.store, KEY_SESSIONS_NEEDING_BACKUP) || {};
-        for(const session of sessions) {
+        const sessionsNeedingBackup
+              = getJsonItem(this.store, KEY_SESSIONS_NEEDING_BACKUP) || {};
+        for (const session of sessions) {
             sessionsNeedingBackup[session.senderKey + '/' + session.sessionId] = true;
         }
         setJsonItem(
-            this.store, KEY_SESSION_NEEDING_BACKUP, sessionsNeedinBackup,
+            this.store, KEY_SESSIONS_NEEDING_BACKUP, sessionsNeedingBackup,
         );
         return Promise.resolve();
     }
diff --git a/src/crypto/store/memory-crypto-store.js b/src/crypto/store/memory-crypto-store.js
index cd5ec5be4..6af312219 100644
--- a/src/crypto/store/memory-crypto-store.js
+++ b/src/crypto/store/memory-crypto-store.js
@@ -315,15 +315,17 @@ export default class MemoryCryptoStore {
     }
 
     unmarkSessionsNeedingBackup(sessions) {
-        for(const session of sessions) {
-            delete this._sessionsNeedingBackup[session.senderKey + '/' + session.sessionId];
+        for (const session of sessions) {
+            const sessionKey = session.senderKey + '/' + session.sessionId;
+            delete this._sessionsNeedingBackup[sessionKey];
         }
         return Promise.resolve();
     }
 
     markSessionsNeedingBackup(sessions) {
-        for(const session of sessions) {
-            this._sessionsNeedingBackup[session.senderKey + '/' + session.sessionId] = true;
+        for (const session of sessions) {
+            const sessionKey = session.senderKey + '/' + session.sessionId;
+            this._sessionsNeedingBackup[sessionKey] = true;
         }
         return Promise.resolve();
     }