I was noticing that the KoboTouchExtended, Kepub Input, Kepub Output, Kepub Metadata Reader and Kepub Metadata Writer plugins were all removed. An attempt to reinstall gave an ImportError message similar to the one from the KoboTouchExtended driver. This seems to be an issue with the import line in _init_.py.
Code:
from calibre_plugins.kobotouch_extended.device.driver import KOBOTOUCHEXTENDED
from calibre_plugins.kepubin.conversion.kepub_input import KEPUBInput
from calibre_plugins.kepubout.conversion.kepub_output import KEPubOutput
from calibre_plugins.kepubmdwriter.metadata.writer import name KEPUBMetadataWriter
from calibre_plugins.kepubmdwriter.metadata.writer import KEPUBMetadataWriter
Edit: To be a total pain, they will install in debug mode and survive a calibre shutdown and restart into debug mode. A normal calibre startup happily removes them.
Edit2: Running from source does not let me install. See attached image.