Plugin management in Gnome is suboptimal; it depends on a given package being in your distro's repos, which gives no room for new packages. Installing a plugin for Rhythmbox is a real pain in the ass, if it's not in the repos. Why not let the plugin manager download new plugins and install them for you? Something between the current plugin managers and the add/remove apps we have now. Something like the attached mockup. My idea is more or less the same as the plugin manager we have now, only it lets you choose and add plugin repos specific to each application. Then you can browse for plugins maintained by Ubuntu, plugins maintained by the developers of that app, or third-party plugins. Then, clicking a plugin's checkbox actually downloads and installs it. No need to have a specific "epiphany-extensions" package with only a few predefined extensions... you can have any extension available out there. Apt-get and repos magic is great, why not use it with plugins as well?
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