I work on the AMP HTML project, which has custom HTML element names such as "amp-img", "amp-install-serviceworker" or "amp-video". WebStorm highlights these as "Unknown HTML tag".
Is there a way to define and share a list of valid AMP HTML elements (based on https://github.com/ampproject/amphtml/tree/master/extensions) ? This is not an XML situation, and adding Unknown HTML tags (alongside nobr,noembed etc.) or attributes individually to the inspection is a poor solution because we can't easily share those with other developers in the project's source repo.