diff --git a/INSTALL.md b/INSTALL.md
index 82d01fa1f..7171c75a3 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -27,6 +27,7 @@ The installation procedure is as follows:
 3. Set an email address for all users that want to use Mozilla Sync. If the user name is already an email address (e.g. **external_user** app) it will be set automatically when users visit their personal page after installing Mozilla Sync. Note: **Email addresses must be unique!**
 
 ### Sync installation on desktop Firefox
+##### Hint: This will only work in Firefox < 29. But it will remain if you upate it to newest Firefox 34
 
 To init the sync of bookmarks, etc. you have to create an account with a desktop installation of Firefox. If you want to sync other devices (e.q. smart phones) do the following installation steps and than pair your device.