Review for Global English Dictionary by Caspajack
Rated 4 out of 5 stars
I used to use the off line version of Outlook until my company went online with Office.365. Unfortunately that version does not have a spell checker... Go Figure!!!
Anyway after a few weeks of struggling without one, (my spelling sucks). I came across this brilliant little free add-on that does the job perfectly.
Excellent find...
To create your own collections, you must have a Mozilla Add-ons account.