Polyfill URL.parse for PDF.js v5 modern build

doc/changelog.asciidoc

@@ -29,6 +29,11 @@ Changed
     * `qute-bitwarden` now passes your password to the subprocess in an
       environment variable when unlocking your vault, instead of as a command
       line argument. (#7781)
+- New `-D no-system-pdfjs` debug flag to ignore system-wide PDF.js installations
+  for testing.
+- Polyfill for missing `URL.parse` with PDF.js v5 and QtWebEngine < 6.9. Note
+  this is a "best effort" fix and you should be using the "older browsers"
+  ("legacy") build of PDF.js instead.
 
 Fixed
 ~~~~~

qutebrowser/javascript/pdfjs_polyfills.js

@@ -19,4 +19,16 @@ SPDX-License-Identifier: GPL-3.0-or-later
             return { promise, resolve, reject }
         }
     }
+
+    // Chromium 126 / QtWebEngine 6.9
+    // https://caniuse.com/mdn-api_url_parse_static
+    if (typeof URL.parse === "undefined") {
+        URL.parse = function(url, base) {
+            try { 
+                return new URL(url, base);
+            } catch (e) {
+                return null;
+            }
+        }
+    }
 })();