>>>Spell checking unfortunately doesn't work for most WYSIWYG solutions because you're not editing a textbox. In order for that to work the editor itself has to implement the spell checking logic
>>>
>>
>>Mike's suggested solution does not include an editor hosted by the browser; it is the browser itself with contenteditable = true. If I add the attribution spellcheck=true, it enables spellchecking, I see it as I type. The only problem/annoyance so far, is that the right-click menu with correction suggestions appears all the way to the left of the screen, and not under he misspelled word as it should (this might be due to the 2 monitor setup I have here). Just started playing with it, haven't got much farther than that, yet.
>
>And this actually works inside of the Web Browser control? Or in a standalone browser? `spellcheck=true` AFAIK was not supported in IE, but it's been a while and potentially pre IE 11 when I checked.
>

Apparently, it does work in the Web Browser control, in either IE11 or Edge compatibility.
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update:
whatbrowser.org shows Edge 16 regardless of what I set in

<meta http-equivalent = "X-UA-Compatible" content = "IE=11" />

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so, apparently the browser control version is determined by the registry entry only (where the FEATURE_BROWSER_EMULATION is set to 11999)
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