Icon is not showing in menus

This is caused by the fact that the thunderbird library folder is not called 'thunderbird-17.0.11esr', but 'thunderbird-17.0.11'. I've implemented a "hackish" solution (without using sed, awk or cut - because I'm a complete newb) where there is a "friendlyVersion" variable that is simply a carbon copy of the version variable, minus the three last characters.