Hi Tom Opgenorth,
You can spellcheck the items of the select element but you cannot update the values of the inner option tags, because the spellchecker is designed to correct the text of form input / textbox / textarea elements only.
What you can do is to implement your own custom text source that will help you to spellcheck the select options and after getting the returned by the spellchecker suggestion using the get_text method to programmatically update the item values of the select elements. See these articles for more information:
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