Could you add the MIME type text/rtf as alias for application/rtf? Some applications that are older than or exist outside of the freedesktop.org realm use the former type. This causes annoying behavior in practice, and the fix is small and simple. IANA lists both, so both uses are valid in general. See KDE bug 159948 for additional discussion.
* freedesktop.org.xml.in: Add text/rtf as an alias for application/rtf (Closes: #16270)
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