In iNotes 8.5.1 there is no way to switch text direction to go from right to left in iNotes rich text field in mail body, as could be done in older versions of DWA /iNotes
In newer versions of DWA/iNotes the browser language selected, must be a bidirectional language, in order for the Bi-Di button to appear.
Resolving the problem
Issue was reported to development in SPR # NKEY7S6EPA and is fixed in 8.5.2
The button should appear if you choose e.g Arabic or Hebrew in the browser setting.
It was found in Firefox the text direction buttons doesn't appear at all even in Hebrew locale. Development advised that the direction button was not supported in Firefox at that time.