The filter for loading downloaded plugins in Calibre seems to be broken.
The official manual for creating plugins says that plugins should bi in zip format with the appropriate init.py file. However the filter on the GUI for loading plugins (Preferences -> Plugins (under advanced) -> Load plugins from file) puts up a filter for filetypes of type "Plugins" and doesn't display any files. This seems to be an error in the configuration, but I do not know how to fix it. I'm using the version of Calibre in the current Ubuntu release repositories (0.8.8), unity interface. The problem has been documented elsewhere and it suggests this has been fixed in the most recent version, but I'm not sure what the best solution is (e.g. I'd rather not use versions of packages setup outside the Ubuntu package manager that won't receive the automatic updates, etc).
Any suggestions for the best work-around?