Rated 3 out of 5 stars

All well and good, but I need to edit descriptions of bookmarks more than anything else. Is there any other bookmark addon that does this?

This review is for a previous version of the add-on (2.2.3.1-signed). 

This addon can do it with hidden preferences

To show description of bookmark popup, you will need to make change to a preference. Open about:config in a new tab. Check 'I'll be careful' and click ok. On preferences list type extensions.editbookmarkplus.showDescription in the search box. Now double click the prefernce to change its value to true.

Once the value is set to True, you should see the description field.