I would suggest checking out Eclipse Che (eclipse.org/che) - Che would meet all of the upside expectations you listed.
Che can be used with any programing language, it's cloud based and is independent of local resources, it's shareable, it has a very comprehensive IDE built in but also allows you to SSH into the workspace and keep using your familiar IDE, and finally it's open source which allows for unlimited customization from you or your organization.
Also for your JS stuff the Che comes with Intellisence because it's default JS editor is Orion.
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I would suggest checking out Eclipse Che (eclipse.org/che) - Che would meet all of the upside expectations you listed. Che can be used with any programing language, it's cloud based and is independent of local resources, it's shareable, it has a very comprehensive IDE built in but also allows you to SSH into the workspace and keep using your familiar IDE, and finally it's open source which allows for unlimited customization from you or your organization. Also for your JS stuff the Che comes with Intellisence because it's default JS editor is Orion.