Sorry for the bug in the first place. It is fixed in the next version (2.0.7) which can be found here: https://addons.mozilla.org/en-US/firefox/addon/fireftp/versions/ (until it is officially reviewed by the Mozilla add-on team)
I appreciate your patience and understanding with the bug - sorry again for the inconvenience.
The Best! You could have the option to only activate it separately. Because sometimes I want to access the FTP through the browser and not through the extension. And it's hard to have to disable the extension, restart Firefox for this.