diff --git a/web/app/components/workflow/nodes/_base/components/editor/base.tsx b/web/app/components/workflow/nodes/_base/components/editor/base.tsx
index 6ed582369c..c0545ff01c 100644
--- a/web/app/components/workflow/nodes/_base/components/editor/base.tsx
+++ b/web/app/components/workflow/nodes/_base/components/editor/base.tsx
@@ -84,7 +84,7 @@ const Base: FC<Props> = ({
 
   return (
     <Wrap className={cn(wrapClassName)} style={wrapStyle} isInNode={isInNode} isExpand={isExpand}>
-      <div ref={ref} className={cn(className, isExpand && 'h-full', 'rounded-lg border', !isFocus ? 'border-transparent bg-components-input-bg-normal' : 'overflow-hidden border-components-input-border-hover bg-components-input-bg-hover')}>
+      <div ref={ref} className={cn(className, isExpand ? 'h-full border-0' : 'rounded-lg border', !isFocus ? 'border-transparent bg-components-input-bg-normal' : 'overflow-hidden border-components-input-border-hover bg-components-input-bg-hover')}>
         <div className="flex h-7 items-center justify-between pl-3 pr-2 pt-1">
           <div className="system-xs-semibold-uppercase text-text-secondary">{title}</div>
           <div
diff --git a/web/app/components/workflow/nodes/_base/hooks/__tests__/use-toggle-expend.spec.ts b/web/app/components/workflow/nodes/_base/hooks/__tests__/use-toggle-expend.spec.ts
new file mode 100644
index 0000000000..266800d9aa
--- /dev/null
+++ b/web/app/components/workflow/nodes/_base/hooks/__tests__/use-toggle-expend.spec.ts
@@ -0,0 +1,123 @@
+import { act, renderHook } from '@testing-library/react'
+import { useRef } from 'react'
+import useToggleExpend from '../use-toggle-expend'
+
+type HookProps = {
+  hasFooter?: boolean
+  isInNode?: boolean
+  clientHeight?: number
+}
+
+/**
+ * Wrapper that provides a real ref whose `.current.clientHeight` is stubbed
+ * so we can verify the height math without a real DOM layout pass.
+ */
+function useHarness({ hasFooter, isInNode, clientHeight = 400 }: HookProps) {
+  const ref = useRef<HTMLDivElement | null>(null)
+
+  // Stub a ref-like object so measurements are deterministic.
+  if (!ref.current) {
+    Object.defineProperty(ref, 'current', {
+      value: { clientHeight } as HTMLDivElement,
+      writable: true,
+    })
+  }
+
+  return useToggleExpend({ ref, hasFooter, isInNode })
+}
+
+describe('useToggleExpend', () => {
+  describe('collapsed state', () => {
+    it('returns empty wrapClassName and zero expand height when collapsed', () => {
+      const { result } = renderHook(() => useHarness({ clientHeight: 400 }))
+
+      expect(result.current.isExpand).toBe(false)
+      expect(result.current.wrapClassName).toBe('')
+      expect(result.current.editorExpandHeight).toBe(0)
+    })
+  })
+
+  describe('expanded state (node context)', () => {
+    it('uses fixed positioning inside a workflow node panel', () => {
+      const { result } = renderHook(() =>
+        useHarness({ isInNode: true, clientHeight: 400 }),
+      )
+
+      act(() => {
+        result.current.setIsExpand(true)
+      })
+
+      expect(result.current.isExpand).toBe(true)
+      expect(result.current.wrapClassName).toContain('fixed')
+      expect(result.current.wrapClassName).toContain('bg-components-panel-bg')
+      expect(result.current.wrapStyle).toEqual(
+        expect.objectContaining({ boxShadow: expect.any(String) }),
+      )
+    })
+  })
+
+  describe('expanded state (execution-log / webapp context)', () => {
+    it('fills its positioned ancestor edge-to-edge without hardcoded offsets', () => {
+      const { result } = renderHook(() =>
+        useHarness({ isInNode: false, clientHeight: 400 }),
+      )
+
+      act(() => {
+        result.current.setIsExpand(true)
+      })
+
+      // The expanded panel must fill the nearest positioned ancestor entirely
+      // (absolute + inset-0). Previously it used hardcoded `top-[52px]` which
+      // assumed a 52px header that does not exist in the conversation-log
+      // layout, causing the expanded panel to overlap the status bar above
+      // the editor (#34887).
+      expect(result.current.wrapClassName).toContain('absolute')
+      expect(result.current.wrapClassName).toContain('inset-0')
+      expect(result.current.wrapClassName).not.toMatch(/top-\[\d+px\]/)
+      expect(result.current.wrapClassName).not.toMatch(/left-\d+/)
+      expect(result.current.wrapClassName).not.toMatch(/right-\d+/)
+      expect(result.current.wrapClassName).toContain('bg-components-panel-bg')
+    })
+  })
+
+  describe('expanded state height math', () => {
+    it('subtracts the 29px chrome when hasFooter is false', () => {
+      const { result } = renderHook(() =>
+        useHarness({ hasFooter: false, clientHeight: 400 }),
+      )
+
+      act(() => {
+        result.current.setIsExpand(true)
+      })
+
+      // 400 (clientHeight) - 29 (title bar) = 371
+      expect(result.current.editorExpandHeight).toBe(371)
+    })
+
+    it('subtracts the 56px chrome when hasFooter is true', () => {
+      const { result } = renderHook(() =>
+        useHarness({ hasFooter: true, clientHeight: 400 }),
+      )
+
+      act(() => {
+        result.current.setIsExpand(true)
+      })
+
+      // 400 (clientHeight) - 56 (title bar + footer) = 344
+      expect(result.current.editorExpandHeight).toBe(344)
+    })
+
+    it('never returns a negative height even if chrome exceeds wrap', () => {
+      const { result } = renderHook(() =>
+        useHarness({ hasFooter: true, clientHeight: 20 }),
+      )
+
+      act(() => {
+        result.current.setIsExpand(true)
+      })
+
+      // 20 - 56 would be -36; clamped to 0.
+      expect(result.current.editorExpandHeight).toBe(0)
+    })
+  })
+})
diff --git a/web/app/components/workflow/nodes/_base/hooks/use-toggle-expend.ts b/web/app/components/workflow/nodes/_base/hooks/use-toggle-expend.ts
index c123c00e2d..1afeb8db12 100644
--- a/web/app/components/workflow/nodes/_base/hooks/use-toggle-expend.ts
+++ b/web/app/components/workflow/nodes/_base/hooks/use-toggle-expend.ts
@@ -1,4 +1,4 @@
-import { useEffect, useState } from 'react'
+import { useLayoutEffect, useState } from 'react'
 
 type Params = {
   ref?: React.RefObject<HTMLDivElement | null>
@@ -6,30 +6,62 @@ type Params = {
   isInNode?: boolean
 }
 
+// Chrome (title bar + optional footer) heights subtracted from the wrap so
+// the editor body never paints underneath its own controls.
+const CHROME_HEIGHT_WITH_FOOTER = 56
+const CHROME_HEIGHT_WITHOUT_FOOTER = 29
+
+/**
+ * Controls the expand/collapse behavior of the code editor wrapper used across
+ * workflow nodes and execution-log panels.
+ *
+ * Returns:
+ *  - `wrapClassName` / `wrapStyle` — positioning + shadow applied to the outer
+ *    wrapper when the editor is expanded.
+ *  - `editorExpandHeight` — height for the editor body (wrap minus chrome).
+ *  - `isExpand` / `setIsExpand` — state + setter for the consumer.
+ *
+ * Height is measured via `useLayoutEffect` so the first expanded render
+ * already has the correct value — the previous `useEffect` implementation
+ * left the editor at the collapsed height for one paint on first expand.
+ */
 const useToggleExpend = ({ ref, hasFooter = true, isInNode }: Params) => {
   const [isExpand, setIsExpand] = useState(false)
-  const [wrapHeight, setWrapHeight] = useState(ref?.current?.clientHeight)
-  const editorExpandHeight = isExpand ? wrapHeight! - (hasFooter ? 56 : 29) : 0
-  useEffect(() => {
+  const [wrapHeight, setWrapHeight] = useState<number | undefined>(undefined)
+
+  useLayoutEffect(() => {
     if (!ref?.current)
       return
-    setWrapHeight(ref.current?.clientHeight)
-  }, [isExpand])
+    setWrapHeight(ref.current.clientHeight)
+  }, [isExpand, ref])
+
+  const chromeHeight = hasFooter ? CHROME_HEIGHT_WITH_FOOTER : CHROME_HEIGHT_WITHOUT_FOOTER
+  const editorExpandHeight = isExpand && wrapHeight !== undefined
+    ? Math.max(0, wrapHeight - chromeHeight)
+    : 0
 
   const wrapClassName = (() => {
     if (!isExpand)
       return ''
 
     if (isInNode)
-      return 'fixed z-10  right-[9px] top-[166px] bottom-[8px]  p-4 bg-components-panel-bg rounded-xl'
+      return 'fixed z-10 right-[9px] top-[166px] bottom-[8px] p-4 bg-components-panel-bg rounded-xl'
 
-    return 'absolute z-10 left-4 right-6 top-[52px] bottom-0 pb-4 bg-components-panel-bg'
+    // Fill the nearest positioned ancestor entirely. Previously hardcoded
+    // `top-[52px] left-4 right-6` offsets assumed a 52px header above the
+    // scroll container — that assumption no longer holds in the conversation
+    // log (result-panel) layout, where the status bar above the editor is
+    // taller than 52px, causing the expanded panel to partially overlap the
+    // status bar (issue #34887).
+    return 'absolute z-10 inset-0 pb-4 bg-components-panel-bg'
   })()
+
   const wrapStyle = isExpand
     ? {
         boxShadow: '0px 0px 12px -4px rgba(16, 24, 40, 0.05), 0px -3px 6px -2px rgba(16, 24, 40, 0.03)',
       }
     : {}
+
   return {
     wrapClassName,
     wrapStyle,