Rated 4 out of 5 stars

Please update this to 3.0b3 or higher.
To get rid of the "0kb" next to the accountname add:
if (size == 0) {
size = "";
units = "";
right before the string:
return String(size) + units;

This will also effect folders with no size like Trash, but now it looks almost like it should be.

This review is for a previous version of the add-on (0.2).