Disable Markdown quoting/copying for Microsoft Edge

Edge crashes around the time the document fragment prepared for Markdown
syntax is inserted into the DOM to get its string representation.

Until we figure out what exactly crashes Edge, this disables Markdown
quoting and copying for that browser.

Author: mislav

quote-selection.js

@@ -5,6 +5,8 @@ import rangeToMarkdown from './markdown-parsing'
 const containers = new WeakMap()
 let installed = 0
 
+const edgeBrowser = /\bEdge\//.test(navigator.userAgent)
+
 type Subscription = {|
   unsubscribe: () => void
 |}
@@ -22,7 +24,9 @@ export function install(container: Element) {
   installed += containers.has(container) ? 0 : 1
   containers.set(container, 1)
   document.addEventListener('keydown', quoteSelection)
-  container.addEventListener('copy', onCopy)
+  if (!edgeBrowser) {
+    container.addEventListener('copy', onCopy)
+  }
 }
 
 export function uninstall(container: Element) {
@@ -31,7 +35,9 @@ export function uninstall(container: Element) {
   if (!installed) {
     document.removeEventListener('keydown', quoteSelection)
   }
-  container.removeEventListener('copy', onCopy)
+  if (!edgeBrowser) {
+    container.removeEventListener('copy', onCopy)
+  }
 }
 
 function onCopy(event: ClipboardEvent) {
@@ -142,7 +148,7 @@ function extractQuote(text: string, range: Range, unwrap: boolean): ?Quote {
   if (!container) return
 
   const markdownSelector = container.getAttribute('data-quote-markdown')
-  if (markdownSelector != null) {
+  if (markdownSelector != null && !edgeBrowser) {
     try {
       selectionText = selectFragment(rangeToMarkdown(range, markdownSelector, unwrap))
         .replace(/^\n+/, '')