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[1] Allow extended attributes to apply to types (#286) (domenic著, ) <https://github.com/heycam/webidl/commit/faaaaa9ffb548a303db362a09e4b1504c4605e0c>

[2] Fix Web IDL extended attribute usage for recent changes (domenic著, ) <https://github.com/whatwg/html/commit/793ace83447c9420a4dbc14f9bb14d3c35550f0a>