And we shouldn't forget the lessons from bug 1414084 for that, i.e. the component that keeps track of which page actions etc. are currently existing needs to match the lifetime webextensions (and therefore Gecko) themselves.
Bug 1530402 Comment 1 Edit History
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And we shouldn't forget the lessons from bug 1414084 for that, i.e. the component that keeps track of which page actions etc. are currently existing needs to match the lifetime of webextensions (and therefore Gecko) themselves.