First, Firefox does some weird things when you try to install BBLog via the download button and when you have already a installed version of BBLog.
Firefox cache the old BBLog version, so you can't update it.
The fix is, clear your complete firefox cache and download the file again.
Weird, yes, but it is so.
Contextmenu
Thx to Nano for the contextmenu information.
In Firefox you can deactivate the contextmenu, when you have deactivated it the BBLog Contextmenu doesn't work.
Here is the correct settings to make it working.
Make sure that the shown checkbox is checked.
Goto Firefox Settings -> Javascript -> Extended