Fix stale image contexts after chat input removal

src/web-ui/src/flow_chat/components/ChatInput.tsx

@@ -551,10 +551,17 @@ export const ChatInput: React.FC<ChatInputProps> = ({
     }
   }, [currentSessionId, workspacePath, derivedState?.isProcessing]);
 
-  const handleInputChange = useCallback((text: string) => {
+  const handleInputChange = useCallback((text: string, activeContexts: import('../../shared/types/context').ContextItem[]) => {
     if (!inputState.isActive && text.length > 0) {
       dispatchInput({ type: 'ACTIVATE' });
     }
+
+    const activeContextIds = new Set(activeContexts.map(context => context.id));
+    contexts.forEach(context => {
+      if (!activeContextIds.has(context.id)) {
+        removeContext(context.id);
+      }
+    });
 
     dispatchInput({ type: 'SET_VALUE', payload: text });
 
@@ -578,7 +585,7 @@ export const ChatInput: React.FC<ChatInputProps> = ({
         });
       }
     }
-  }, [derivedState, setQueuedInput, inputState.isActive, slashCommandState.isActive]);
+  }, [contexts, derivedState, inputState.isActive, removeContext, setQueuedInput, slashCommandState.isActive]);
 
   const handleSendOrCancel = useCallback(async () => {
     if (!derivedState) return;

src/web-ui/src/flow_chat/components/RichTextInput.tsx

@@ -302,13 +302,20 @@ export const RichTextInput = React.forwardRef<HTMLDivElement, RichTextInputProps
     if (isComposingRef.current) return;
 
     const textContent = extractTextContent();
-    onChange(textContent, contexts);
+    const visibleContextIds = new Set(
+      Array.from(internalRef.current?.querySelectorAll<HTMLElement>('[data-context-id]') ?? [])
+        .map(element => element.dataset.contextId)
+        .filter((id): id is string => !!id)
+    );
+    const visibleContexts = contexts.filter(context => visibleContextIds.has(context.id));
+
+    onChange(textContent, visibleContexts);
 
     // Ensure detection runs after DOM updates
     requestAnimationFrame(() => {
       detectMention();
     });
-  }, [contexts, onChange, detectMention]);
+  }, [contexts, onChange, detectMention, internalRef]);
 
   const handlePaste = useCallback((e: React.ClipboardEvent) => {
     e.preventDefault();