[1] HTMLFrameSetElement
HTMLFrameSetElement
border
borderColor
cols
frameBorder
frameSpacing
name
onafterprint
HTMLFrameSetElement2
onbeforeprint
onbeforeunload
onload
onunload
rows
[2] Fix which built-in elements can be customized (domenic著, 11/16/2016, 4:31:58 PM) <https://github.com/whatwg/html/commit/7d6b279b0d2bc30752700155a043b65441fe12e3>
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