Updated links regarding dom.event.clipboardevents.enabled & dom.allow…

…_cut_copy

README.md

@@ -180,8 +180,8 @@ HTML5 / [APIs](https://wiki.mozilla.org/WebAPI) / [DOM](https://en.wikipedia.org
 * Disable battery API (Firefox < 52) [ [1](https://developer.mozilla.org/en-US/docs/Web/API/BatteryManager) [2](https://bugzilla.mozilla.org/show_bug.cgi?id=1313580) ]
 * Disable telephony API [ [1](https://wiki.mozilla.org/WebAPI/Security/WebTelephony) ]
 * Disable "beacon" asynchronous HTTP transfers (used for analytics) [ [1](https://developer.mozilla.org/en-US/docs/Web/API/navigator.sendBeacon) ]
-* Disable clipboard event detection (onCut/onCopy/onPaste) via Javascript
-* Disable "copy to clipboard" functionality via Javascript (Firefox >= 41)
+* Disable clipboard event detection (onCut/onCopy/onPaste) via Javascript [ [1](https://web.archive.org/web/20210416195937/https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/Preference_reference/dom.event.clipboardevents.enabled) [2](https://github.com/pyllyukko/user.js/issues/287) ]
+* Disable "copy to clipboard" functionality via Javascript (Firefox >= 41) [ [1](https://hg.mozilla.org/mozilla-central/rev/2f9f8ea4b9c3) [2](https://github.com/pyllyukko/user.js/issues/287) ]
 * Disable speech recognition [ [1](https://dvcs.w3.org/hg/speech-api/raw-file/tip/speechapi.html) [2](https://developer.mozilla.org/en-US/docs/Web/API/SpeechRecognition) [3](https://wiki.mozilla.org/HTML5_Speech_API) ]
 * Disable speech synthesis [ [1](https://developer.mozilla.org/en-US/docs/Web/API/SpeechSynthesis) ]
 * Disable sensor API [ [1](https://wiki.mozilla.org/Sensor_API) ]

user.js

@@ -110,13 +110,15 @@ user_pref("dom.telephony.enabled", false);
 user_pref("beacon.enabled", false);
 
 // PREF: Disable clipboard event detection (onCut/onCopy/onPaste) via Javascript
+// https://web.archive.org/web/20210416195937/https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/Preference_reference/dom.event.clipboardevents.enabled
+// https://github.com/pyllyukko/user.js/issues/287
 // NOTICE: Disabling clipboard events breaks Ctrl+C/X/V copy/cut/paste functionaility in JS-based web applications (Google Docs...)
-// https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/Preference_reference/dom.event.clipboardevents.enabled
 user_pref("dom.event.clipboardevents.enabled", false);
 
 // PREF: Disable "copy to clipboard" functionality via Javascript (Firefox >= 41)
-// NOTICE: Disabling clipboard operations will break legitimate JS-based "copy to clipboard" functionality
 // https://hg.mozilla.org/mozilla-central/rev/2f9f8ea4b9c3
+// https://github.com/pyllyukko/user.js/issues/287
+// NOTICE: Disabling clipboard operations will break legitimate JS-based "copy to clipboard" functionality
 user_pref("dom.allow_cut_copy", false);
 
 // PREF: Disable speech recognition