chore: Updated to firefox 142.0, p=#9870

* chore: Updateed to firefox 142.0, b=no-bug, c=l10n, folders

* chore: Finish updating to firefox, b=no-bug, c=tabs

* chore: Fixed mods builds, b=no-bug, c=mods

* feat: Small changes to tabs layout, b=no-bug, c=tabs, compact-mode, folders, workspaces

* test: Fixed tests, b=no-bug, c=scripts, tests, folders

* test: Fixed tests, b=no-bug, c=tabs, tests, welcome

scripts/run_tests.py

@@ -4,10 +4,33 @@
 
 import os
 import sys
+import json
 from pathlib import Path
 
+IGNORE_PREFS_FILE_IN = os.path.join(
+    'src', 'zen', 'tests', 'ignorePrefs.json'
+)
+IGNORE_PREFS_FILE_OUT = os.path.join(
+    'engine', 'testing', 'mochitest', 'ignorePrefs.json'
+)
+
+
+def copy_ignore_prefs():
+  print("Copying ignorePrefs.json from src/zen/tests to engine/testing/mochitest...")
+  # if there are prefs that dont exist on output file, copy them from input file
+  all_prefs = []
+  with open(IGNORE_PREFS_FILE_OUT, 'r') as f:
+    all_prefs = json.load(f)
+    with open(IGNORE_PREFS_FILE_IN, 'r') as f_in:
+      new_prefs = json.load(f_in)
+      all_prefs.extend(p for p in new_prefs if p not in all_prefs)
+  with open(IGNORE_PREFS_FILE_OUT, 'w') as f_out:
+    json.dump(all_prefs, f_out, indent=2)
+
 
 def main():
+  copy_ignore_prefs()
+
   project_root = Path(__file__).resolve().parent.parent
   package_json = project_root / 'package.json'