diff --git a/src/renderer/src/components/terminal-pane/pty-connection.test.ts b/src/renderer/src/components/terminal-pane/pty-connection.test.ts
index 90069139515..74180bee1a7 100644
--- a/src/renderer/src/components/terminal-pane/pty-connection.test.ts
+++ b/src/renderer/src/components/terminal-pane/pty-connection.test.ts
@@ -12103,6 +12103,28 @@ describe('connectPanePty', () => {
       return { transport, pane, dataCallback: capturedDataCallback.current!, binding }
     }
 
+    // STA-4042 root: the restore-needed marker is the ONE point where "bytes
+    // were dropped" is known. The emulator carries state across chunks just like
+    // the cross-chunk parser the handler already resets, so the gap is closed
+    // here rather than left to each recovery path to remember.
+    it('closes the emulator state gap when a drop is announced', async () => {
+      enableMainAuthority()
+      const deps = createDeps({ isVisibleRef: { current: false } })
+      const { pane, dataCallback } = await connectHiddenPane(deps)
+      dataCallback('hidden output\r\n', { seq: 16, rawLength: 16 })
+      pane.terminal.write.mockClear()
+
+      const { _dispatchPtyModelRestoreNeededForTest } = await import('./pty-model-restore-channel')
+      _dispatchPtyModelRestoreNeededForTest({ id: 'pty-id', reason: 'hidden-drop', markerSeq: 64 })
+      await flushAsyncTicks(4)
+
+      const written = pane.terminal.write.mock.calls.map(([data]) => data as string)
+      const gapReset = written.find((data) => data.startsWith('\x1b[0m'))
+      expect(gapReset).toBeDefined()
+      // charset too: a dropped ESC(B otherwise renders text as box characters
+      expect(gapReset).toContain('\x1b(B')
+    })
+
     it('marks the PTY hidden on hidden output and clears it before requesting restore on reveal', async () => {
       enableMainAuthority()
       const deps = createDeps({ isVisibleRef: { current: false } })
diff --git a/src/renderer/src/components/terminal-pane/pty-connection.ts b/src/renderer/src/components/terminal-pane/pty-connection.ts
index 8c770f48fdc..fefcd24816a 100644
--- a/src/renderer/src/components/terminal-pane/pty-connection.ts
+++ b/src/renderer/src/components/terminal-pane/pty-connection.ts
@@ -6101,6 +6101,14 @@ export function connectPanePty(
       })
       // Why: dropped bytes invalidate cross-chunk carry — a partial OSC-9999 prefix spanning the gap would corrupt the next live chunk.
       transport.resetCrossChunkParserState?.()
+      // Why the emulator too: it carries state across chunks exactly like the
+      // parser does. If the gap swallowed the `ESC[22m` closing a bold run (or
+      // the `ESC(B` leaving line-drawing), every cell written afterwards
+      // inherits it. This marker is the one point where "bytes were dropped" is
+      // known, so close the state gap here instead of relying on each recovery
+      // path to remember — restore, abandon and overflow then all start from a
+      // known pen (STA-4042).
+      writePtyOutputToXterm(RESET_AFTER_BYTE_GAP, true)
       // Why gated (rc.7.perf loop): on a visible pane these markers come from our own restore starving ACKs; re-arming per marker kept the fetch loop alive all flood, so defer to one post-flood repaint.
       if (isForegroundRestoreBackpressureContext()) {
         noteHiddenOutputRestoreFloodBackpressure()