title: Word taskpane add-in is disabled when working with an rtf or odt document
body: <p>I am trying to develop a Word add-in which is written in JS and makes use of the OfficeJS library. When I open an rtf or odt file, the taskpane button to open the add-in is disabled. However, the plugin runs fine when working with docx files.</p>
  <p><a href="https://i.stack.imgur.com/fAlIx.png" rel="nofollow noreferrer">Takepane button when looking at odt</a></p>
  <p>The Office add-in documentation doesn't make me aware of any limitations regarding the aforementioned file types.</p>
  <p>Does anyone have any workarounds to get this working?</p>