Issue only happens when using webengine

Check if using webengine, before trying to use thw workaround

qutebrowser/browser/browsertab.py

@@ -560,7 +560,6 @@ class AbstractTab(QWidget):
         self._mouse_event_filter = mouse.MouseEventFilter(
             self, widget_class=self.WIDGET_CLASS, parent=self)
         self.backend = None
-        self.needs_qtbug54419_workaround = False
 
         # FIXME:qtwebengine  Should this be public api via self.hints?
         #                    Also, should we get it out of objreg?

qutebrowser/browser/webengine/webenginetab.py

@@ -472,6 +472,7 @@ class WebEngineTab(browsertab.AbstractTab):
         # init js stuff
         self._init_js()
         self._child_event_filter = None
+        self.needs_qtbug54419_workaround = False
 
     def _init_js(self):
         js_code = '\n'.join([

qutebrowser/mainwindow/tabbedbrowser.py

@@ -521,7 +521,8 @@ class TabbedBrowser(tabwidget.TabWidget):
 
         # If needed, re-open the tab as a workaround for QTBUG-54419.
         # See https://bugreports.qt.io/browse/QTBUG-54419
-        if tab.needs_qtbug54419_workaround:
+        if (tab.backend == usertypes.Backend.QtWebEngine and
+            tab.needs_qtbug54419_workaround):
             log.misc.debug("Doing QTBUG-54419 workaround for {}, "
                            "url {}".format(tab, url))
             self.setUpdatesEnabled(False)