Enable Firefox Check Spelling on single line text-boxes forever?

Question

As you know we can enable spell checker on single line Text-Boxes with following way:

We have to enable it every time for checking words.

How we can enable it forever so it doesn't need to be enabled each time ?

Answer 1

To change how Firefox checks spelling and enable spell-checking on one-line and multi-line text fields, use about:config to set layout.spellcheckDefault to 2.

To edit your configuration, type about:config in the address bar and press Enter.

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