I have found and downloaded a spelling add-on but cannot find where it is insatalled and/or accessed.
Where do you put the downloaded add-ons? I lost the spell checker I had with previous version so looked for one on your add-on page which I downloaded but cannot find where it is accessed. THE FOLLOWING IS WHAT I FOUND IN YOUR LIST
After the Deadline - Spell and Grammar Checker by Automattic, mitcho (Michael 芳貴 Erlewine)
Add to Firefox
Rated 4 out of 5 stars 32 reviews
After the Deadline is an intelligent grammar, style, and spell checker. It works with most web sites.
To solve this problem I recommend contact developer of this add-on.