This extension is very useful and I use it all the time. However, there is an annoying bug with the icon popup in the current version - it does not respect the "Open search page in" setting under preferences. Even if you have that setting set to "a background tab" (and not "a background tab next to current tab") the extension opens search results in a background tab next to the current tab ...

Hmm ... actually looks as if even the context-menu does not respect the "Open search page in" setting - it used to in the previous version but I have not used the context menu since the popup was added ...