we can use the old undo shortcut on 5.11

webviews no longer propagate the captured shortcut

aqt/browser.py

@@ -417,6 +417,8 @@ class Browser(QMainWindow):
         f.filter.clicked.connect(self.onFilterButton)
         # edit
         f.actionUndo.triggered.connect(self.mw.onUndo)
+        if qtminor < 11:
+            f.actionUndo.setShortcut(QKeySequence(_("Ctrl+Alt+Z")))
         f.actionInvertSelection.triggered.connect(self.invertSelection)
         f.actionSelectNotes.triggered.connect(self.selectNotes)
         if not isMac:

aqt/main.py

@@ -890,6 +890,8 @@ title="%s" %s>%s</button>''' % (
         m.actionPreferences.triggered.connect(self.onPrefs)
         m.actionAbout.triggered.connect(self.onAbout)
         m.actionUndo.triggered.connect(self.onUndo)
+        if qtminor < 11:
+            m.actionUndo.setShortcut(QKeySequence(_("Ctrl+Alt+Z")))
         m.actionFullDatabaseCheck.triggered.connect(self.onCheckDB)
         m.actionCheckMediaDatabase.triggered.connect(self.onCheckMediaDB)
         m.actionDocumentation.triggered.connect(self.onDocumentation)

designer/browser.ui

@@ -341,7 +341,7 @@
     <string>&amp;Undo</string>
    </property>
    <property name="shortcut">
-    <string>Ctrl+Alt+Z</string>
+    <string>Ctrl+Z</string>
    </property>
   </action>
   <action name="actionInvertSelection">

designer/main.ui

@@ -134,7 +134,7 @@
     <string>&amp;Undo</string>
    </property>
    <property name="shortcut">
-    <string>Ctrl+Alt+Z</string>
+    <string>Ctrl+Z</string>
    </property>
   </action>
   <action name="actionCheckMediaDatabase">