Not opening in new tab Rated 4 out of 5 stars

I am getting a white blank tab, as if we click a new tab button, opened when i left click the Quickfox Notes icon.Right click is working well and i am getting Quickfox Notes in a separate window for that. Is this behavior due to installation of any other Add-on? I am using 3.5.7 version...Pls help...

This review is for a previous version of the add-on (2.1C).