Really effective add on to make gmail easier to use without opening additional tabs.
I really wish I could mute it though, the audible notifications are an un-welcomed nuisance when streaming for friends, colleagues or just when I'm not at computer but hear a loud notification form my computer anyways. The options to reduce volume does not fix it, unticking the box to 'Play alert sound for new emails' does not fix it and 4 months now no response from support request for help.