Add resend button for 30s

frontend/src/App.tsx

@@ -666,6 +666,18 @@ export function App() {
     }
   }, []);
 
+  // Handle resend channel message
+  const handleResendChannelMessage = useCallback(async (messageId: number) => {
+    try {
+      await api.resendChannelMessage(messageId);
+      toast.success('Message resent');
+    } catch (err) {
+      toast.error('Failed to resend', {
+        description: err instanceof Error ? err.message : 'Unknown error',
+      });
+    }
+  }, []);
+
   // Handle sender click to add mention
   const handleSenderClick = useCallback((sender: string) => {
     messageInputRef.current?.appendText(`@[${sender}] `);
@@ -1182,6 +1194,9 @@ export function App() {
                       activeConversation.type === 'channel' ? handleSenderClick : undefined
                     }
                     onLoadOlder={fetchOlderMessages}
+                    onResendChannelMessage={
+                      activeConversation.type === 'channel' ? handleResendChannelMessage : undefined
+                    }
                     radioName={config?.name}
                     config={config}
                   />

frontend/src/api.ts

@@ -166,6 +166,10 @@ export const api = {
       method: 'POST',
       body: JSON.stringify({ channel_key: channelKey, text }),
     }),
+  resendChannelMessage: (messageId: number) =>
+    fetchJson<{ status: string; message_id: number }>(`/messages/channel/${messageId}/resend`, {
+      method: 'POST',
+    }),
 
   // Packets
   getUndecryptedPacketCount: () => fetchJson<{ count: number }>('/packets/undecrypted/count'),

frontend/src/components/MessageList.tsx

@@ -23,6 +23,7 @@ interface MessageListProps {
   hasOlderMessages?: boolean;
   onSenderClick?: (sender: string) => void;
   onLoadOlder?: () => void;
+  onResendChannelMessage?: (messageId: number) => void;
   radioName?: string;
   config?: RadioConfig | null;
 }
@@ -134,6 +135,8 @@ function HopCountBadge({ paths, onClick, variant }: HopCountBadgeProps) {
   );
 }
 
+const RESEND_WINDOW_SECONDS = 30;
+
 export function MessageList({
   messages,
   contacts,
@@ -142,6 +145,7 @@ export function MessageList({
   hasOlderMessages = false,
   onSenderClick,
   onLoadOlder,
+  onResendChannelMessage,
   radioName,
   config,
 }: MessageListProps) {
@@ -153,6 +157,8 @@ export function MessageList({
     paths: MessagePath[];
     senderInfo: SenderInfo;
   } | null>(null);
+  const [resendableIds, setResendableIds] = useState<Set<number>>(new Set());
+  const resendTimersRef = useRef<Map<number, ReturnType<typeof setTimeout>>>(new Map());
 
   // Capture scroll state in the scroll handler BEFORE any state updates
   const scrollStateRef = useRef({
@@ -216,6 +222,43 @@ export function MessageList({
     }
   }, [messages.length]);
 
+  // Track resendable outgoing CHAN messages (within 30s window)
+  useEffect(() => {
+    if (!onResendChannelMessage) return;
+
+    const now = Math.floor(Date.now() / 1000);
+    const newResendable = new Set<number>();
+    const timers = resendTimersRef.current;
+
+    for (const msg of messages) {
+      if (!msg.outgoing || msg.type !== 'CHAN' || msg.sender_timestamp === null) continue;
+      const remaining = RESEND_WINDOW_SECONDS - (now - msg.sender_timestamp);
+      if (remaining <= 0) continue;
+
+      newResendable.add(msg.id);
+
+      // Schedule removal if not already tracked
+      if (!timers.has(msg.id)) {
+        const timer = setTimeout(() => {
+          setResendableIds((prev) => {
+            const next = new Set(prev);
+            next.delete(msg.id);
+            return next;
+          });
+          timers.delete(msg.id);
+        }, remaining * 1000);
+        timers.set(msg.id, timer);
+      }
+    }
+
+    setResendableIds(newResendable);
+
+    return () => {
+      for (const timer of timers.values()) clearTimeout(timer);
+      timers.clear();
+    };
+  }, [messages, onResendChannelMessage]);
+
   // Handle scroll - capture state and detect when user is near top/bottom
   const handleScroll = useCallback(() => {
     if (!listRef.current) return;
@@ -463,11 +506,23 @@ export function MessageList({
                       )}
                     </>
                   )}
+                  {msg.outgoing && onResendChannelMessage && resendableIds.has(msg.id) && (
+                    <button
+                      className="text-muted-foreground hover:text-primary ml-1 text-xs cursor-pointer"
+                      onClick={(e) => {
+                        e.stopPropagation();
+                        onResendChannelMessage(msg.id);
+                      }}
+                      title="Resend message"
+                    >
+                      ↻
+                    </button>
+                  )}
                   {msg.outgoing &&
                     (msg.acked > 0 ? (
                       msg.paths && msg.paths.length > 0 ? (
                         <span
-                          className="cursor-pointer hover:text-primary"
+                          className="text-muted-foreground cursor-pointer hover:text-primary"
                           onClick={(e) => {
                             e.stopPropagation();
                             setSelectedPath({
@@ -483,10 +538,13 @@ export function MessageList({
                           title="View echo paths"
                         >{` ✓${msg.acked > 1 ? msg.acked : ''}`}</span>
                       ) : (
-                        ` ✓${msg.acked > 1 ? msg.acked : ''}`
+                        <span className="text-muted-foreground">{` ✓${msg.acked > 1 ? msg.acked : ''}`}</span>
                       )
                     ) : (
-                      <span title="No repeats heard yet"> ?</span>
+                      <span className="text-muted-foreground" title="No repeats heard yet">
+                        {' '}
+                        ?
+                      </span>
                     ))}
                 </div>
               </div>

frontend/src/components/SettingsModal.tsx

@@ -123,7 +123,6 @@ export function SettingsModal(props: SettingsModalProps) {
   const [cr, setCr] = useState('');
   const [privateKey, setPrivateKey] = useState('');
   const [maxRadioContacts, setMaxRadioContacts] = useState('');
-  const [experimentalChannelDoubleSend, setExperimentalChannelDoubleSend] = useState(false);
 
   // Loading states
   const [busySection, setBusySection] = useState<SettingsSection | null>(null);
@@ -202,7 +201,6 @@ export function SettingsModal(props: SettingsModalProps) {
   useEffect(() => {
     if (appSettings) {
       setMaxRadioContacts(String(appSettings.max_radio_contacts));
-      setExperimentalChannelDoubleSend(appSettings.experimental_channel_double_send);
       setAutoDecryptOnAdvert(appSettings.auto_decrypt_dm_on_advert);
       setAdvertInterval(String(appSettings.advert_interval));
       setBots(appSettings.bots || []);
@@ -368,9 +366,6 @@ export function SettingsModal(props: SettingsModalProps) {
       if (!isNaN(newMaxRadioContacts) && newMaxRadioContacts !== appSettings?.max_radio_contacts) {
         update.max_radio_contacts = newMaxRadioContacts;
       }
-      if (experimentalChannelDoubleSend !== appSettings?.experimental_channel_double_send) {
-        update.experimental_channel_double_send = experimentalChannelDoubleSend;
-      }
       if (Object.keys(update).length > 0) {
         await onSaveAppSettings(update);
       }
@@ -900,27 +895,6 @@ export function SettingsModal(props: SettingsModalProps) {
                 </p>
               </div>
 
-              <div className="p-3 bg-yellow-500/10 border border-yellow-500/30 rounded-md space-y-3">
-                <p className="text-sm text-yellow-500">
-                  <strong>Experimental:</strong> Adds a duplicate channel send after a 3-second
-                  delay, using the exact same timestamp bytes.
-                </p>
-                <label className="flex items-center gap-3 cursor-pointer">
-                  <input
-                    type="checkbox"
-                    checked={experimentalChannelDoubleSend}
-                    onChange={(e) => setExperimentalChannelDoubleSend(e.target.checked)}
-                    className="w-4 h-4 rounded border-input accent-primary"
-                  />
-                  <span className="text-sm">Always send channel messages twice</span>
-                </label>
-                <p className="text-xs text-muted-foreground">
-                  This increases channel airtime and adds a 3-second second-attempt delay. Most
-                  clients deduplicate repeats by payload and timestamp, but behavior can vary by
-                  firmware/client.
-                </p>
-              </div>
-
               <Button
                 onClick={handleSaveConnectivity}
                 disabled={isSectionBusy('connectivity')}

frontend/src/test/appFavorites.test.tsx

@@ -182,7 +182,6 @@ const baseConfig = {
 
 const baseSettings = {
   max_radio_contacts: 200,
-  experimental_channel_double_send: false,
   favorites: [] as Array<{ type: 'channel' | 'contact'; id: string }>,
   auto_decrypt_dm_on_advert: false,
   sidebar_sort_order: 'recent' as const,

frontend/src/test/appStartupHash.test.tsx

@@ -158,7 +158,6 @@ describe('App startup hash resolution', () => {
     });
     mocks.api.getSettings.mockResolvedValue({
       max_radio_contacts: 200,
-      experimental_channel_double_send: false,
       favorites: [],
       auto_decrypt_dm_on_advert: false,
       sidebar_sort_order: 'recent',

frontend/src/test/settingsModal.test.tsx

@@ -36,7 +36,6 @@ const baseHealth: HealthStatus = {
 
 const baseSettings: AppSettings = {
   max_radio_contacts: 200,
-  experimental_channel_double_send: false,
   favorites: [],
   auto_decrypt_dm_on_advert: false,
   sidebar_sort_order: 'recent',
@@ -194,24 +193,6 @@ describe('SettingsModal', () => {
     });
   });
 
-  it('saves experimental channel double-send toggle through onSaveAppSettings', async () => {
-    const { onSaveAppSettings } = renderModal({
-      appSettings: { ...baseSettings, experimental_channel_double_send: false },
-    });
-
-    openConnectivitySection();
-
-    const toggle = screen.getByLabelText('Always send channel messages twice');
-    fireEvent.click(toggle);
-    fireEvent.click(screen.getByRole('button', { name: 'Save Settings' }));
-
-    await waitFor(() => {
-      expect(onSaveAppSettings).toHaveBeenCalledWith({
-        experimental_channel_double_send: true,
-      });
-    });
-  });
-
   it('renders selected section from external sidebar nav on desktop mode', async () => {
     renderModal({
       externalSidebarNav: true,

frontend/src/types.ts

@@ -124,7 +124,6 @@ export interface BotConfig {
 
 export interface AppSettings {
   max_radio_contacts: number;
-  experimental_channel_double_send: boolean;
   favorites: Favorite[];
   auto_decrypt_dm_on_advert: boolean;
   sidebar_sort_order: 'recent' | 'alpha';
@@ -137,7 +136,6 @@ export interface AppSettings {
 
 export interface AppSettingsUpdate {
   max_radio_contacts?: number;
-  experimental_channel_double_send?: boolean;
   auto_decrypt_dm_on_advert?: boolean;
   sidebar_sort_order?: 'recent' | 'alpha';
   advert_interval?: number;