If it´s complicated, then we can just ignore this. 
Translations will be at 99%, they will show a blank space in English and that’s it.
Actually it isn’t an empty string, it has space. Transifex doesn’t accept a space as a translation of a space (seriously, although I can see the point).
What is the function of that space? Can it be either eliminated or converted in really an empty string "" (which maybe it is ignored by Transifex)?
As said, if this is too much trouble for a space then let’s just leave it.