I think what we should do here is reject any attempt to load from `content://` URIs from in-content, leaving top-level as the only way to load a `content://` URIs. So HTML/images etc will still load in Fennec but all sub-resource will be broken.
Bug 1647078 Comment 21 Edit History
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I think what we should do here is reject any attempt to load from `content://` URIs from in-content, leaving top-level as the only way to load a `content://` URIs. So top-level HTML/images etc will still load in Fennec but all sub-resources will be broken.