If Firefox is set via about:config to: "browser.tabs.closeWindowWithLastTab" False, then after installing this addon and restarting Firefox, the page will then continually reload.
If I reset "browser.tabs.closeWindowWithLastTab" to True, then this behavior stops, but I don't want it set to True, so I have gone back to using version 0.3.4.
Opening the Add-ons tab via Firefox Tools/Add-ons, while about:config "browser.tabs.closeWindowWithLastTab" is set to False, should be enough to duplicate the page reload problem, if not try clicking on the last tab close button, then maximizing the Add-ons tab again.
Also setting the page to open about:home gives an invalid page error and opens nothing.
*[Using Firefox 3.6.28]* and sticking with it, as this old PC can't run the latest versions of Firefox.
*I won't down rate this Add-on because the old version works just fine and it has been very useful to me.