diff --git a/kitty/file_transmission.py b/kitty/file_transmission.py
index cef518834..9cead0df2 100644
--- a/kitty/file_transmission.py
+++ b/kitty/file_transmission.py
@@ -1058,13 +1058,14 @@ class FileTransmission:
                 'The remote machine wants to read some files from this computer. Do you want to allow the transfer?'
                 )],
                 window=window, custom_callback=partial(self.handle_receive_confirmation, asd_id),
+                default_data={'response': 'n'}
             )
 
     def handle_receive_confirmation(self, cmd_id: str, data: Dict[str, str], *a: Any) -> None:
         asd = self.active_sends.get(cmd_id)
         if asd is None:
             return
-        if data['response'] == 'y':
+        if data.get('response') == 'y':
             asd.accepted = True
         else:
             self.drop_send(asd.id)
@@ -1089,13 +1090,14 @@ class FileTransmission:
                 'The remote machine wants to send some files to this computer. Do you want to allow the transfer?'
                 )],
                 window=window, custom_callback=partial(self.handle_send_confirmation, ar_id),
+                default_data={'response': 'n'}
             )
 
     def handle_send_confirmation(self, cmd_id: str, data: Dict[str, str], *a: Any) -> None:
         ar = self.active_receives.get(cmd_id)
         if ar is None:
             return
-        if data['response'] == 'y':
+        if data.get('response') == 'y':
             ar.accepted = True
         else:
             self.drop_receive(ar.id)
diff --git a/kitty/window.py b/kitty/window.py
index 9554ae9b0..dfd39b5ee 100644
--- a/kitty/window.py
+++ b/kitty/window.py
@@ -659,13 +659,14 @@ class Window:
                     '--choice=o:Open', '--choice=c:Copy to clipboard', '--choice=n;red:Nothing'
                     ],
                     window=self,
-                    custom_callback=partial(self.hyperlink_open_confirmed, url, cwd)
+                    custom_callback=partial(self.hyperlink_open_confirmed, url, cwd),
+                    default_data={'response': ''}
                 )
                 return
         get_boss().open_url(url, cwd=cwd)
 
     def hyperlink_open_confirmed(self, url: str, cwd: Optional[str], data: Dict[str, Any], *a: Any) -> None:
-        q = data['response']
+        q = data.get('response', '')
         if q == 'o':
             get_boss().open_url(url, cwd=cwd)
         elif q == 'c':
@@ -912,14 +913,15 @@ class Window:
             'A program running in this window wants to read from the system clipboard.'
             ' Allow it do so, once?')],
             window=self,
-            custom_callback=self.handle_clipboard_confirmation
+            custom_callback=self.handle_clipboard_confirmation,
+            default_data={'response': 'n'}
         )
 
     def handle_clipboard_confirmation(self, data: Dict[str, Any], *a: Any) -> None:
         try:
             loc = 'p' if self.current_clipboard_read_ask else 'c'
             response = ''
-            if data['response'] == 'y':
+            if data.get('response') == 'y':
                 response = get_primary_selection() if self.current_clipboard_read_ask else get_clipboard_string()
             self.send_osc52(loc, response)
         finally: