At the [moment](https://github.com/lemon24/reader/blob/58fd95be80d10b73e2097e292501be1f276d79a7/reader/app.py#L171), the enclosure tag proxy is enabled if `requests` and `mutagen` are available, and there's no way to turn it off short of uninstalling them. Ideally, some sort of plug-in interface should be devised for this kind of stuff.
