Header removals wait for the code editor to be left: autosave saves with drop=false, so follow_header adds and renames from the header but keeps a port or setting whose parameter is gone, and leaving the editor (blur or closing the panel) saves once more with removals; source saves of a flow run one at a time

frontend/src/components/Flow/FlowEditor.tsx

@@ -865,7 +865,15 @@ function FlowEditorInner({
   })
 
   const sourceMutation = useMutation({
-    mutationFn: async ({ nodeId, code }: { nodeId: string; code: string }) => {
+    mutationFn: async ({
+      nodeId,
+      code,
+      drop,
+    }: {
+      nodeId: string
+      code: string
+      drop?: boolean
+    }) => {
       // The server reads the ports off the header and compares them with its
       // draft, so the ports on the canvas have to be there first.
       await flush()
@@ -873,8 +881,12 @@ function FlowEditorInner({
         name: flowName,
         nodeId,
         requestBody: { code },
+        drop,
       })
     },
+    // One at a time: the save that drops a port must not land before the
+    // autosave that kept it.
+    scope: { id: `source:${flowName}` },
     onSuccess: (saved) => {
       const followed = saved.node
       if (followed && saved.version) {
@@ -1454,8 +1466,9 @@ function FlowEditorInner({
         onToggleExpand={() => setEditorExpanded((wide) => !wide)}
         onChange={updateNode}
         onRenameMessage={proposeRename}
-        onSaveSource={(code) => {
-          if (selected) sourceMutation.mutate({ nodeId: selected.id, code })
+        onSaveSource={(code, drop) => {
+          if (selected)
+            sourceMutation.mutate({ nodeId: selected.id, code, drop })
         }}
         // Sharing rewrites the stored document, so the canvas takes the
         // server's copy rather than keeping its own.