Open updater toast changelog links externally (#4970)

* fix: Hook into markdown-generated anchors to avoid e.g breaking the desktop app

* add comment

* Disable eslint on copied line from ts-stack

---------

Co-authored-by: marc2332 <mespinsanz@gmail.com>

src/lib/markdown.ts

@@ -0,0 +1,52 @@
+import { MarkedOptions, Renderer, unescape } from '@ts-stack/markdown'
+import { openExternalBrowserIfDesktop } from './openWindow'
+
+/**
+ * Main goal of this custom renderer is to prevent links from changing the current location
+ * this is specially important for the desktop app.
+ */
+export class SafeRenderer extends Renderer {
+  constructor(options: MarkedOptions) {
+    super(options)
+
+    // Attach a global function for non-react anchor elements that need safe navigation
+    window.openExternalLink = (e: React.MouseEvent<HTMLAnchorElement>) => {
+      openExternalBrowserIfDesktop()(e)
+    }
+  }
+
+  // Extended from https://github.com/ts-stack/markdown/blob/c5c1925c1153ca2fe9051c356ef0ddc60b3e1d6a/packages/markdown/src/renderer.ts#L116
+  link(href: string, title: string, text: string): string {
+    if (this.options.sanitize) {
+      let prot: string
+
+      try {
+        prot = decodeURIComponent(unescape(href))
+          .replace(/[^\w:]/g, '')
+          .toLowerCase()
+      } catch (e) {
+        return text
+      }
+
+      if (
+        // eslint-disable-next-line no-script-url
+        prot.indexOf('javascript:') === 0 ||
+        prot.indexOf('vbscript:') === 0 ||
+        prot.indexOf('data:') === 0
+      ) {
+        return text
+      }
+    }
+
+    let out =
+      '<a onclick="openExternalLink(event)" target="_blank" href="' + href + '"'
+
+    if (title) {
+      out += ' title="' + title + '"'
+    }
+
+    out += '>' + text + '</a>'
+
+    return out
+  }
+}