fix(coding-agent): restored windows image paste fallback

Fell back to the PowerShell clipboard bridge when the native Windows clipboard reader reports no image, preserving Ctrl+V image paste in PowerShell terminals.\n\nFixes #2429

packages/coding-agent/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Fixed Windows PowerShell image paste so Ctrl+V can fall back to the PowerShell clipboard bridge when the native clipboard reader reports no image ([#2429](https://github.com/can1357/oh-my-pi/issues/2429)).
+
 ## [15.12.3] - 2026-06-12
 
 ### Fixed

packages/coding-agent/src/utils/clipboard.ts

@@ -66,9 +66,10 @@ export async function copyToClipboard(text: string): Promise<void> {
 	}
 }
 
-// PowerShell one-liner that emits the clipboard image as base64-encoded PNG on
-// stdout, or nothing when the clipboard does not hold image data. Used as the
-// WSL bridge — arboard cannot read the Windows clipboard through WSLg.
+// PowerShell one-liner that emits the Windows clipboard image as base64-encoded
+// PNG on stdout, or nothing when the clipboard does not hold image data. Used
+// for native Windows fallback and WSL interop because arboard can miss host
+// clipboard image payloads in those terminal paths.
 const POWERSHELL_IMAGE_SCRIPT = `
 $ErrorActionPreference = 'Stop'
 Add-Type -AssemblyName System.Windows.Forms
@@ -84,31 +85,36 @@ if ($img -ne $null) {
 const POWERSHELL_TIMEOUT_MS = 8000;
 
 /**
- * Read a clipboard image through the Windows host's PowerShell.
+ * Read an image through the Windows host's PowerShell.
  *
- * WSLg exposes a Wayland socket but no native clipboard image transport, so
- * `arboard` returns `ContentNotAvailable`. PowerShell, reached via WSL interop,
- * can read the Windows clipboard directly and round-trip the bitmap as PNG.
+ * Native Windows uses this as a fallback when arboard reports no image or
+ * cannot access the clipboard. WSLg exposes a Wayland socket but no native
+ * clipboard image transport, so arboard returns `ContentNotAvailable` there;
+ * PowerShell, reached via WSL interop, can read the Windows clipboard directly
+ * and round-trip the bitmap as PNG.
  *
  * Returns null when no image is on the clipboard, the host PowerShell is
  * missing, or the bridge times out.
  */
 async function readImageViaPowerShell(): Promise<ClipboardImage | null> {
 	try {
-		const proc = Bun.spawn(["powershell.exe", "-NoProfile", "-NonInteractive", "-Command", POWERSHELL_IMAGE_SCRIPT], {
-			stdout: "pipe",
-			stderr: "ignore",
-			stdin: "ignore",
-		});
+		const proc = Bun.spawn(
+			["powershell.exe", "-NoProfile", "-NonInteractive", "-Sta", "-Command", POWERSHELL_IMAGE_SCRIPT],
+			{
+				stdout: "pipe",
+				stderr: "ignore",
+				stdin: "ignore",
+			},
+		);
 		const timer = setTimeout(() => proc.kill(), POWERSHELL_TIMEOUT_MS);
 		let stdout = "";
 		try {
 			stdout = await new Response(proc.stdout).text();
 			await proc.exited;
 		} catch (err) {
-			// powershell.exe is a Windows process reached over WSL interop; if it
-			// doesn't reap cleanly, swallow the error so the dispatcher can fall
-			// through to the native bridge instead of throwing.
+			// powershell.exe can be a Windows process reached either natively or
+			// over WSL interop; if it doesn't reap cleanly, report no image instead
+			// of surfacing an opaque bridge failure to the prompt.
 			logger.warn("clipboard: powershell read failed", { error: String(err) });
 			return null;
 		} finally {
@@ -179,9 +185,10 @@ async function readTextViaPowerShell(): Promise<string | null> {
  * Read an image from the system clipboard.
  *
  * Returns null on Termux (no image clipboard support) or when no display
- * server is available (headless/SSH without forwarding). Under WSL the
- * Windows clipboard is reached through `powershell.exe`, since WSLg's
- * Wayland clipboard does not carry image payloads through to `arboard`.
+ * server is available (headless/SSH without forwarding). Under native Windows
+ * and WSL, the Windows clipboard is also reached through `powershell.exe`
+ * because terminal clipboard paths can leave image payloads invisible to the
+ * native bridge.
  *
  * @returns PNG payload or null when no image is available.
  */
@@ -198,6 +205,16 @@ export async function readImageFromClipboard(): Promise<ClipboardImage | null> {
 		// no display, so arboard would reject anyway.
 	}
 
+	if (process.platform === "win32") {
+		try {
+			const image = await native.readImageFromClipboard();
+			if (image) return image;
+		} catch (err) {
+			logger.warn("clipboard: native Windows image read failed", { error: String(err) });
+		}
+		return await readImageViaPowerShell();
+	}
+
 	if (!hasDisplay()) {
 		return null;
 	}

packages/coding-agent/test/utils/clipboard.test.ts

@@ -147,6 +147,21 @@ describe("readImageFromClipboard dispatch", () => {
 		expect(nativeSpy).not.toHaveBeenCalled();
 	});
 
+	it("uses the PowerShell bridge on native Windows when arboard has no image payload", async () => {
+		setPlatform("win32");
+		const calls: SpawnCall[] = [];
+		spyPowershell(calls, RED_1X1_PNG_BASE64);
+		vi.spyOn(native, "readImageFromClipboard").mockResolvedValue(null);
+
+		const image = await readImageFromClipboard();
+
+		expect(calls).toHaveLength(1);
+		expect(calls[0]?.cmd[0]).toBe("powershell.exe");
+		expect(image?.mimeType).toBe("image/png");
+		expect(Array.from(image!.data.subarray(0, 8))).toEqual([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]);
+		expect(calls[0]?.cmd).toContain("-Sta");
+	});
+
 	it("delegates straight to the native bridge on non-WSL linux with a display", async () => {
 		setPlatform("linux");
 		process.env.DISPLAY = ":0";