[1] IRC logs: freenode / #whatwg / 20081207 ( 版) <http://krijnhoetmer.nl/irc-logs/whatwg/20081207#l-206>
文脈メニューが表示されるタイミングが環境によって異なるので (Mac では mousedown、 Windows では mouseup)、 contextmenu が発火されるタイミングも環境依存。
[2] HTML5 context menus in Firefox (Screencast and Code) ✩ Mozilla Hacks – the Web developer blog ( 版) <https://hacks.mozilla.org/2011/11/html5-context-menus-in-firefox-screencast-and-code/>
[3] Editorial: synchronize with the DOM Standard · whatwg/html@21c6ec7 ( 版) <https://github.com/whatwg/html/commit/21c6ec77594eb89b836d4872222f5916910967fd>
[4] Remove <button type=menu> (domenic著, ) <https://github.com/whatwg/html/commit/916e1b9f6bea48cb117ddd056ea025adaa629384>
[5] Editorial: contextmenu uses MouseEvent (SaschaNaz著, ) <https://github.com/whatwg/html/commit/74976ccad3e4332ad921b624c2c55219173336e9>
[6] Remove the context menu feature (domenic著, ) <https://github.com/whatwg/html/commit/e7e8c88ecdd7cdc96171f05ab6fe23b56dd48d8a>
[7] Treat trusted contextmenu events as user activation (mustaqahmed著, ) <https://github.com/whatwg/html/commit/51bd770cf58cdd761674df0f47c9f9dfc58c5310>
[8] Treat trusted `contextmenu` events as user activation. by mustaqahmed · Pull Request #3659 · whatwg/html () <https://github.com/whatwg/html/pull/3659>