I haven't read every single post about the Kindle Fire so I apologize if this has been discussed elsewhere.
The books that are in mobi format in my Calibre Library are being transferred to the Documents folder on my Fire when I do a transfer to device but then cannot be viewed/read. I did a quick little experiment and did a direct copy of the same file but with the mobi extension changed to prc. I put it into the Books file on the Fire so that I could differentiate which was sent through Calibre and which I just copied directly. The prc file showed up in the Books section of the Fire and opened. The mobi file was nowhere to be seen unless I opened up the file in a File Explorer (on the Fire) or in Explorer (on my computer) and it couldn't be read on the Fire.
Is there a plug-in that will do this change automatically and put the file in the Fire folder that we would designate (Newsstand, Books, Docs)?
If not, I think that it would be a great idea. (even though this isn't the Plug-in idea section)