A couple of html table related methods in lib.d.ts return HTMLElement, but they could return a more precise type:

• HTMLTableElement.insertRow should return HTMLTableRowElement instead of HTMLElement
• HTMLTableElement.createTHead should return HTMLTableSectionElement instead of HTMLElement
• HTMLTableElement.createTBody should return HTMLTableSectionElement instead of HTMLElement
• HTMLTableElement.createTFoot should return HTMLTableSectionElement instead of HTMLElement
• HTMLTableElement.createCaption should return HTMLTableCaptionElement instead of HTMLElement
• HTMLTableSectionElement.insertRow should return HTMLTableRowElement instead of HTMLElement
• HTMLTableRowElement.insertCell should return HTMLTableCellElement instead of HTMLElement