You're going to love this answer mate...
SMF has always used a server-side programme called pspell to spellcheck posts as the user writes them. Unfortunately for the authors of pspell, PHP is advancing so fast nowadays that they just don't seem to be able to keep up and are doomed.
As most browsers have built-in spellcheck nowadays, this is obviously the way to go.
The above is being checked by my Firefox browser as I type - right-clicking on the red underlined words suggests an alternative and/or offers "Add to Dictionary"
Steve
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