avoid popups for some non-serious warnings

aqt/main.py

@@ -292,7 +292,7 @@ close the profile or restart Anki."""))
                 if getattr(w, "silentlyClose", None):
                     w.close()
                 else:
-                    showWarning("Window should have been closed: {}".format(w))
+                    print("Window should have been closed: {}".format(w))
 
     def unloadProfileAndExit(self):
         self.unloadProfile(self.cleanupAndExit)

aqt/webview.py

@@ -75,7 +75,7 @@ class AnkiWebPage(QWebEnginePage):
         # catch buggy <a href='#' onclick='func()'> links
         from aqt import mw
         if url.matches(QUrl(mw.serverURL()), QUrl.RemoveFragment):
-            sys.stderr.write("onclick handler needs to return false\n")
+            print("onclick handler needs to return false")
             return False
         # load all other links in browser
         openLink(url)