Apply suggestions from code review

Co-authored-by: Elliott Sales de Andrade <quantum.analyst@gmail.com>

Author: scottshambaugh

lib/matplotlib/backends/backend_webagg_core.py

@@ -350,10 +350,10 @@ def _handle_key(self, event):
 
     def handle_toolbar_button(self, event):
         name = event['name']
-        allowed = {item[3] for item in self.toolbar.toolitems if item[3] is not None}
-        if name not in allowed:
-            return
-        getattr(self.toolbar, name)()
+        for item in self.toolbar.toolitems:
+            if item[3] is not None and name == item[3]:
+                getattr(self.toolbar, name)()
+                break
 
     def handle_refresh(self, event):
         if self.manager:

lib/matplotlib/tests/test_backend_webagg.py

@@ -1,6 +1,7 @@
 import os
 import sys
 from unittest.mock import MagicMock
+
 import pytest
 
 import matplotlib.backends.backend_webagg_core