LazyTY and Poll come already installed. After I vagrant ssh’d and cloned a plugin into /vagrant/plugins, I can’t seem to get the plugin to activate.
LazyYT doesn’t need to be “activated” and poll is already “activated” (cf. the “Y” in the Enabled? column).
Im sorry, i meant to say LazyYT and Poll come already activated. I wanted to activate the other 2 which are grey’d out.
Those are old plugins that might not support the new API to enable/disable a plugin. If they’re not broken, they should already be working 
Also the fact that some are blue and some are just black/gray text simply indicates if a URL was given in the plugin.rb file for that given plugin. It doesn’t mean enabled/disabled.
That must be it. i wasn’t aware of those facts. After using the search feature under settings, I did find their settings but it seems they are not supported by the current version as you mentioned. Thanks anyway 
This is not the first time I’ve seen this confuse people. We might want to have it so that if a plugin doesn’t support the API is displays active (with no toggle). It’s less confusing.
This commit should hopefully make it clearer 
https://github.com/discourse/discourse/commit/0e02e0272d19f4e152deea6b258149573e8b0532