diff --git a/src/shared/binary-downloader.ts b/src/shared/binary-downloader.ts
index a44206c2e..a36c4a89a 100644
--- a/src/shared/binary-downloader.ts
+++ b/src/shared/binary-downloader.ts
@@ -4,6 +4,7 @@ import { spawn } from "./bun-spawn-shim";
 import { bunWrite } from "./bun-file-shim";
 import { validateArchiveEntries, type ArchiveEntry } from "./archive-entry-validator";
 import { extractZip } from "./zip-extractor";
+import { readProcessStream } from "./process-stream-reader";
 
 function isTarTraversalErrorOutput(output: string): boolean {
   return /path contains '\.\.'|member name contains '\.\.'|removing leading [`'\"]?\.\.\//i.test(output)
@@ -47,7 +48,8 @@ export async function extractTarGz(
 
   const exitCode = await proc.exited;
   if (exitCode !== 0) {
-    const stderr = await new Response(proc.stderr).text();
+    // #3919: Avoid Response(stream).text() in Windows Desktop utility processes.
+    const stderr = await readProcessStream(proc.stderr);
 
     if (isTarTraversalErrorOutput(stderr)) {
       throw new Error(`Unsafe archive entry: path contains path traversal (${archivePath})`)
@@ -107,8 +109,9 @@ async function listTarEntries(archivePath: string, cwd?: string): Promise<Archiv
 
   const [exitCode, stdout, stderr] = await Promise.all([
     proc.exited,
-    new Response(proc.stdout).text(),
-    new Response(proc.stderr).text(),
+    // #3919: Use Buffer-concat stream reads for Node utility-process compatibility.
+    readProcessStream(proc.stdout),
+    readProcessStream(proc.stderr),
   ])
 
   if (isTarTraversalErrorOutput(stderr)) {
diff --git a/src/shared/ripgrep-cli.ts b/src/shared/ripgrep-cli.ts
index 5f62b3ad7..3ee9b8a22 100644
--- a/src/shared/ripgrep-cli.ts
+++ b/src/shared/ripgrep-cli.ts
@@ -20,12 +20,19 @@ let autoInstallAttempted = false
 
 function findExecutable(name: string): string | null {
   const isWindows = process.platform === "win32"
-  const cmd = isWindows ? "where" : "which"
+  const cmd = isWindows ? "where.exe" : "which"
 
   try {
-    const result = spawnSync(cmd, [name], { encoding: "utf-8", timeout: 5000 })
-    if (result.status === 0 && result.stdout.trim()) {
-      return result.stdout.trim().split("\n")[0]
+    // #3919: Keep Windows executable probes hidden and shell-free in Desktop utility processes.
+    const result = spawnSync(cmd, [name], {
+      encoding: "utf-8",
+      timeout: 5000,
+      windowsHide: isWindows,
+      shell: false,
+    })
+    const stdout = result.stdout
+    if (result.status === 0 && stdout.trim()) {
+      return stdout.trim().split("\n")[0]
     }
   } catch {
     return null
diff --git a/src/shared/zip-entry-listing/powershell-zip-entry-listing.ts b/src/shared/zip-entry-listing/powershell-zip-entry-listing.ts
index a77213899..4d465df4a 100644
--- a/src/shared/zip-entry-listing/powershell-zip-entry-listing.ts
+++ b/src/shared/zip-entry-listing/powershell-zip-entry-listing.ts
@@ -1,6 +1,7 @@
 import { spawn } from "../bun-spawn-shim"
 
 import type { ArchiveEntry } from "../archive-entry-validator"
+import { readProcessStream } from "../process-stream-reader"
 
 export type PowerShellZipExtractor = "pwsh" | "powershell"
 
@@ -82,8 +83,9 @@ export async function listZipEntriesWithPowerShell(
 
 	const [exitCode, stdout, stderr] = await Promise.all([
 		proc.exited,
-		new Response(proc.stdout).text(),
-		new Response(proc.stderr).text(),
+		// #3919: Use Buffer-concat stream reads for Node utility-process compatibility.
+		readProcessStream(proc.stdout),
+		readProcessStream(proc.stderr),
 	])
 
 	if (exitCode !== 0) {
diff --git a/src/shared/zip-entry-listing/python-zip-entry-listing.ts b/src/shared/zip-entry-listing/python-zip-entry-listing.ts
index 4cdd71610..b322ff6d6 100644
--- a/src/shared/zip-entry-listing/python-zip-entry-listing.ts
+++ b/src/shared/zip-entry-listing/python-zip-entry-listing.ts
@@ -1,6 +1,7 @@
 import { spawn, spawnSync } from "../bun-spawn-shim"
 
 import type { ArchiveEntry } from "../archive-entry-validator"
+import { readProcessStream } from "../process-stream-reader"
 
 export function isPythonZipListingAvailable(): boolean {
 	const proc = spawnSync(["python3", "--version"], {
@@ -43,8 +44,9 @@ export async function listZipEntriesWithPython(
 
 	const [exitCode, stdout, stderr] = await Promise.all([
 		proc.exited,
-		new Response(proc.stdout).text(),
-		new Response(proc.stderr).text(),
+		// #3919: Use Buffer-concat stream reads for Node utility-process compatibility.
+		readProcessStream(proc.stdout),
+		readProcessStream(proc.stderr),
 	])
 
 	if (exitCode !== 0) {
diff --git a/src/shared/zip-entry-listing/read-zip-symlink-target.ts b/src/shared/zip-entry-listing/read-zip-symlink-target.ts
index 2b6b9ab8d..63de96e69 100644
--- a/src/shared/zip-entry-listing/read-zip-symlink-target.ts
+++ b/src/shared/zip-entry-listing/read-zip-symlink-target.ts
@@ -1,4 +1,5 @@
 import { spawn } from "../bun-spawn-shim"
+import { readProcessStream } from "../process-stream-reader"
 
 export async function readZipSymlinkTarget(
 	archivePath: string,
@@ -11,8 +12,9 @@ export async function readZipSymlinkTarget(
 
 	const [exitCode, stdout, stderr] = await Promise.all([
 		proc.exited,
-		new Response(proc.stdout).text(),
-		new Response(proc.stderr).text(),
+		// #3919: Use Buffer-concat stream reads for Node utility-process compatibility.
+		readProcessStream(proc.stdout),
+		readProcessStream(proc.stderr),
 	])
 
 	if (exitCode !== 0) {
diff --git a/src/shared/zip-entry-listing/tar-zip-entry-listing.ts b/src/shared/zip-entry-listing/tar-zip-entry-listing.ts
index f346b6552..5add6a139 100644
--- a/src/shared/zip-entry-listing/tar-zip-entry-listing.ts
+++ b/src/shared/zip-entry-listing/tar-zip-entry-listing.ts
@@ -2,6 +2,7 @@ import { spawn } from "../bun-spawn-shim"
 
 import type { ArchiveEntry } from "../archive-entry-validator"
 import { log } from "../logger"
+import { readProcessStream } from "../process-stream-reader"
 
 
 
@@ -81,8 +82,9 @@ export async function listZipEntriesWithTar(
 
 	const [exitCode, stdout, stderr] = await Promise.all([
 		proc.exited,
-		new Response(proc.stdout).text(),
-		new Response(proc.stderr).text(),
+		// #3919: Use Buffer-concat stream reads for Node utility-process compatibility.
+		readProcessStream(proc.stdout),
+		readProcessStream(proc.stderr),
 	])
 
 	if (exitCode !== 0) {
diff --git a/src/shared/zip-entry-listing/zipinfo-zip-entry-listing.ts b/src/shared/zip-entry-listing/zipinfo-zip-entry-listing.ts
index 926e8b5da..b61c5efc3 100644
--- a/src/shared/zip-entry-listing/zipinfo-zip-entry-listing.ts
+++ b/src/shared/zip-entry-listing/zipinfo-zip-entry-listing.ts
@@ -1,6 +1,7 @@
 import { spawn, spawnSync } from "../bun-spawn-shim"
 
 import type { ArchiveEntry } from "../archive-entry-validator"
+import { readProcessStream } from "../process-stream-reader"
 import { readZipSymlinkTarget } from "./read-zip-symlink-target"
 
 export function parseZipInfoListedEntry(line: string): ArchiveEntry | null {
@@ -45,8 +46,9 @@ export async function listZipEntriesWithZipInfo(
 
 	const [exitCode, stdout, stderr] = await Promise.all([
 		proc.exited,
-		new Response(proc.stdout).text(),
-		new Response(proc.stderr).text(),
+		// #3919: Use Buffer-concat stream reads for Node utility-process compatibility.
+		readProcessStream(proc.stdout),
+		readProcessStream(proc.stderr),
 	])
 
 	if (exitCode !== 0) {
diff --git a/src/shared/zip-extractor.ts b/src/shared/zip-extractor.ts
index cdc61fecc..d8a6710f6 100644
--- a/src/shared/zip-extractor.ts
+++ b/src/shared/zip-extractor.ts
@@ -1,7 +1,8 @@
-import { spawn, spawnSync } from "./bun-spawn-shim"
+import { spawn, spawnSync, type SpawnedProcess } from "./bun-spawn-shim"
 import { release } from "os"
 
 import { validateArchiveEntries } from "./archive-entry-validator"
+import { readProcessStream } from "./process-stream-reader"
 import {
 	isPythonZipListingAvailable,
 	isZipInfoZipListingAvailable,
@@ -53,7 +54,7 @@ export async function extractZip(archivePath: string, destDir: string): Promise<
   const entries = await listZipEntries(archivePath)
   validateArchiveEntries(entries, destDir)
 
-  let proc
+  let proc: SpawnedProcess
   
   if (process.platform === "win32") {
     const extractor = getWindowsZipExtractor()
@@ -89,7 +90,8 @@ export async function extractZip(archivePath: string, destDir: string): Promise<
   const exitCode = await proc.exited
   
   if (exitCode !== 0) {
-    const stderr = await new Response(proc.stderr).text()
+    // #3919: Avoid Response(stream).text() in Windows Desktop utility processes.
+    const stderr = await readProcessStream(proc.stderr)
     throw new Error(`zip extraction failed (exit ${exitCode}): ${stderr}`)
   }
 }