In some cases, Parsoid seems to be adding both mw:ExpandedAttrs and mw:Transclusion type to dom nodes. This really doesn't make that much sense. mw:Transclusion is a stronger assertion about the node than a mw:ExpandedAttrs and should override it. This matters because clients like that don't yet support mw:ExpandedAttrs will refuse to make such nodes editable even though mw:Transclusion nodes are editable.

This can happen because ext.core.AttributeExpander doesn't check for the proper type. Or, it could happen when template ranges are merged / expanded during template wrapping.

So, worth auditing code and fixing it.