Your extension should be updated automatically. However, in some cases, you might need to conduct a manual update.
How to update a wallet in Chrome:
1. Visit your Chrome extension page: chrome://extensions or click the right button on the extensions widget and choose "Manage extensions"
2. Select Temple
3. Click "Update"
How to update a wallet in Firefox:
1. Right click on Temple icon
2. Choose "Manage Extension"
3. Click on a cogwheel "Check updates"
That's all.