You selected content marking. That is why you have no spell checker.

Type about:config<enter> in the address bar. If a warning screen comes up, press the I Accept the Risk button. At the top of the screen is a search bar.

Type: layout.spellcheckDefault Its values are; 0 Spell Checker Off 1 Check Only Multi-Line Input Boxes. 2 Check Multi And Single Line Input Boxes.

Also, check the spellchecker.dictionary entry.

Many thanks FredMcd.

Is there anyway to save changes made in about:config I set the value for layout.spellcheckDefault at 2 And restarted the PC

Still not working, specifically in email apps, Gmail, and Outlook.

But working in this chatbox !!!

The difference between the default 1 and 2 is that 2 also enables the spell checker for single line input field like a search field.

The web page can disable the Firefox spell checker via a spellcheck="false" attribute of an input field or textarea or editable element and possibly provide its own spelling checker. Firefox will disable Check Spelling in the right-click context menu of a text area if the web page disables the spelling checker via a spellcheck="false" attribute of this element.

You can right-click in the text area or input field and use "Inspect Element" to see if this text area has a spellcheck="false" attribute. Removing this spellcheck="false" attribute or changing it to spellcheck="true" via a double-click or via "Edit As HTML" should make the Check Spelling item in the right-click context menu reappear.

• https://developer.mozilla.org/en-US/Tools/Page_Inspector/How_to/Examine_and_edit_HTML

I created Bug 1671297: Web sites turn off spell checker Need override to stop it

@cor-el: Aha! Thank you for explaining. That makes sense and explains my confusion for so many many years. However, is there no way to choose the layoutSpellCheckDefault setting without breaking into the about:config? Why isn't this exposed in about:preferences? Why is the default 1 and not 2?