debug webengine dll problems

aqt/qt.py

@@ -12,6 +12,9 @@ os.environ["LIBOVERLAY_SCROLLBAR"] = "0"
 from anki.utils import isWin, isMac
 
 from PyQt5.Qt import *
+# trigger explicit message in case of missing libraries
+# instead of silently failing to import
+from PyQt5.QtWebEngineWidgets import QWebEnginePage
 
 def debug():
   from PyQt5.QtCore import pyqtRemoveInputHook