To Enable Automatic Spell Check In All Textboxes And Webforms

By default Firefox's in-line spell checker does not work in all text boxes and forms and you need to right-click and select “Spell check this field” to manually start spell-check, however this behavior can be automatically activated by following the steps provided below.

1. Type about:config in your Firefox address bar and press Enter.
2. Type layout.spell in filter text box.
3. Change the value to 2 as shown below.

Enjoy.................