| PASS Node.prototype.cloneNode(false) must be able to clone a custom element | |
| PASS Node.prototype.cloneNode(false) must be able to clone a custom element inside an iframe | |
| PASS Node.prototype.cloneNode(true) must be able to clone a descendent custom element | |
| PASS Node.prototype.cloneNode(true) must set parentNode, previousSibling, and nextSibling before upgrading custom elements | |
| PASS HTMLElement constructor must throw an InvalidStateError when the top of the construction stack is marked AlreadyConstructed due to a custom element constructor constructing itself after super() call | |
| PASS HTMLElement constructor must throw an InvalidStateError when the top of the construction stack is marked AlreadyConstructed due to a custom element constructor constructing itself before super() call | |
| PASS Upgrading a custom element must throw InvalidStateError when the custom element's constructor returns another element | |
| PASS Inserting an element must not try to upgrade a custom element when it had already failed to upgrade once | |