Hello Kyle Watson,
Thank you for your feedback about the Spell Checker.
As for your HTML import/ export questions:
RadRichTextBox does not have special modes for HTML or the other formats it supports import from/ export to. You have guessed right that not all HTML documents will be rendered as they appear in a browser when imported, but you can easily test if the rich text box handles correctly sample documents of yours in our demo. On the other hand, the export should produce an output very similar to what you see in the editor.
However, worth noting is, that once imported, the documents will be converted to our internal representation, namely RadDocument. Exporting this should look the same, but on the HTML level, will most probably be very different.
If you have other questions, do not hesitate to contact us again.
the Telerik team
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