Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

19 files changed, 1230 insertions, 0 deletions

diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/Factory.cpp b/toolkit/components/aboutthirdparty/tests/TestShellEx/Factory.cpp
new file mode 100644
index 0000000000..a341c27b73
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/Factory.cpp
@@ -0,0 +1,74 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/Atomics.h"
+#include "mozilla/RefPtr.h"
+
+#include <windows.h>
+#include <shlobj.h>
+
+already_AddRefed<IExtractIconW> CreateIconExtension();
+
+class ClassFactory final : public IClassFactory {
+  mozilla::Atomic<uint32_t> mRefCnt;
+
+  ~ClassFactory() = default;
+
+ public:
+  ClassFactory() : mRefCnt(0) {}
+
+  // IUnknown
+
+  STDMETHODIMP QueryInterface(REFIID aRefIID, void** aResult) {
+    if (!aResult) {
+      return E_INVALIDARG;
+    }
+
+    if (aRefIID == IID_IClassFactory) {
+      RefPtr ref(static_cast<IClassFactory*>(this));
+      ref.forget(aResult);
+      return S_OK;
+    }
+
+    return E_NOINTERFACE;
+  }
+
+  STDMETHODIMP_(ULONG) AddRef() { return ++mRefCnt; }
+
+  STDMETHODIMP_(ULONG) Release() {
+    ULONG result = --mRefCnt;
+    if (!result) {
+      delete this;
+    }
+    return result;
+  }
+
+  // IClassFactory
+
+  STDMETHODIMP CreateInstance(IUnknown* aOuter, REFIID aRefIID,
+                              void** aResult) {
+    if (aOuter) {
+      return CLASS_E_NOAGGREGATION;
+    }
+
+    RefPtr<IUnknown> instance;
+    if (IsEqualCLSID(aRefIID, IID_IExtractIconA) ||
+        IsEqualCLSID(aRefIID, IID_IExtractIconW)) {
+      instance = CreateIconExtension();
+    } else {
+      return E_NOINTERFACE;
+    }
+
+    return instance ? instance->QueryInterface(aRefIID, aResult)
+                    : E_OUTOFMEMORY;
+  }
+
+  STDMETHODIMP LockServer(BOOL) { return S_OK; }
+};
+
+already_AddRefed<IClassFactory> CreateFactory() {
+  return mozilla::MakeAndAddRef<ClassFactory>();
+}
diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/Icon.cpp b/toolkit/components/aboutthirdparty/tests/TestShellEx/Icon.cpp
new file mode 100644
index 0000000000..116c0e03a1
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/Icon.cpp
@@ -0,0 +1,109 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/Atomics.h"
+#include "mozilla/RefPtr.h"
+#include "Resource.h"
+
+#include <windows.h>
+#include <shlobj.h>
+
+#include <string>
+
+extern std::wstring gDllPath;
+extern GUID CLSID_TestShellEx;
+
+class IconExtension final : public IPersistFile,
+                            public IExtractIconA,
+                            public IExtractIconW {
+  mozilla::Atomic<uint32_t> mRefCnt;
+
+  ~IconExtension() = default;
+
+ public:
+  IconExtension() : mRefCnt(0) {}
+
+  // IUnknown
+
+  STDMETHODIMP QueryInterface(REFIID aRefIID, void** aResult) {
+    if (!aResult) {
+      return E_INVALIDARG;
+    }
+
+    if (aRefIID == IID_IPersist) {
+      RefPtr ref(static_cast<IPersist*>(this));
+      ref.forget(aResult);
+      return S_OK;
+    } else if (aRefIID == IID_IPersistFile) {
+      RefPtr ref(static_cast<IPersistFile*>(this));
+      ref.forget(aResult);
+      return S_OK;
+    } else if (aRefIID == IID_IExtractIconA) {
+      RefPtr ref(static_cast<IExtractIconA*>(this));
+      ref.forget(aResult);
+      return S_OK;
+    } else if (aRefIID == IID_IExtractIconW) {
+      RefPtr ref(static_cast<IExtractIconW*>(this));
+      ref.forget(aResult);
+      return S_OK;
+    }
+
+    return E_NOINTERFACE;
+  }
+
+  STDMETHODIMP_(ULONG) AddRef() { return ++mRefCnt; }
+
+  STDMETHODIMP_(ULONG) Release() {
+    ULONG result = --mRefCnt;
+    if (!result) {
+      delete this;
+    }
+    return result;
+  }
+
+  // IPersist
+
+  STDMETHODIMP GetClassID(CLSID* aClassID) {
+    *aClassID = CLSID_TestShellEx;
+    return S_OK;
+  }
+
+  // IPersistFile
+
+  STDMETHODIMP GetCurFile(LPOLESTR*) { return E_NOTIMPL; }
+  STDMETHODIMP IsDirty() { return S_FALSE; }
+  STDMETHODIMP Load(LPCOLESTR, DWORD) { return S_OK; }
+  STDMETHODIMP Save(LPCOLESTR, BOOL) { return E_NOTIMPL; }
+  STDMETHODIMP SaveCompleted(LPCOLESTR) { return E_NOTIMPL; }
+
+  // IExtractIconA
+
+  STDMETHODIMP Extract(PCSTR, UINT, HICON*, HICON*, UINT) { return E_NOTIMPL; }
+  STDMETHODIMP GetIconLocation(UINT, PSTR, UINT, int*, UINT*) {
+    return E_NOTIMPL;
+  }
+
+  // IExtractIconW
+
+  STDMETHODIMP Extract(PCWSTR, UINT, HICON*, HICON*, UINT) { return S_FALSE; }
+
+  STDMETHODIMP GetIconLocation(UINT, PWSTR aIconFile, UINT aCchMax, int* aIndex,
+                               UINT* aOutFlags) {
+    if (aCchMax <= gDllPath.size()) {
+      return E_NOT_SUFFICIENT_BUFFER;
+    }
+
+    gDllPath.copy(aIconFile, gDllPath.size());
+    aIconFile[gDllPath.size()] = 0;
+    *aOutFlags = GIL_DONTCACHE;
+    *aIndex = -IDI_ICON1;
+    return S_OK;
+  }
+};
+
+already_AddRefed<IExtractIconW> CreateIconExtension() {
+  return mozilla::MakeAndAddRef<IconExtension>();
+}
diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/RegUtils.cpp b/toolkit/components/aboutthirdparty/tests/TestShellEx/RegUtils.cpp
new file mode 100644
index 0000000000..33b2feb12a
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/RegUtils.cpp
@@ -0,0 +1,148 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/UniquePtr.h"
+#include "RegUtils.h"
+
+#include <windows.h>
+#include <strsafe.h>
+
+extern std::wstring gDllPath;
+
+const wchar_t kClsIdPrefix[] = L"CLSID\\";
+const wchar_t* kExtensionSubkeys[] = {
+    L".zzz\\shellex\\IconHandler",
+};
+
+bool RegKey::SetStringInternal(const wchar_t* aValueName,
+                               const wchar_t* aValueData,
+                               DWORD aValueDataLength) {
+  if (!mKey) {
+    return false;
+  }
+
+  return ::RegSetValueExW(mKey, aValueName, 0, REG_SZ,
+                          reinterpret_cast<const BYTE*>(aValueData),
+                          aValueDataLength) == ERROR_SUCCESS;
+}
+
+RegKey::RegKey(HKEY root, const wchar_t* aSubkey) : mKey(nullptr) {
+  ::RegCreateKeyExW(root, aSubkey, 0, nullptr, 0, KEY_ALL_ACCESS, nullptr,
+                    &mKey, nullptr);
+}
+
+RegKey::~RegKey() {
+  if (mKey) {
+    ::RegCloseKey(mKey);
+  }
+}
+
+bool RegKey::SetString(const wchar_t* aValueName, const wchar_t* aValueData) {
+  return SetStringInternal(
+      aValueName, aValueData,
+      aValueData
+          ? static_cast<DWORD>((wcslen(aValueData) + 1) * sizeof(wchar_t))
+          : 0);
+}
+
+bool RegKey::SetString(const wchar_t* aValueName,
+                       const std::wstring& aValueData) {
+  return SetStringInternal(
+      aValueName, aValueData.c_str(),
+      static_cast<DWORD>((aValueData.size() + 1) * sizeof(wchar_t)));
+}
+
+std::wstring RegKey::GetString(const wchar_t* aValueName) {
+  DWORD len = 0;
+  LSTATUS status = ::RegGetValueW(mKey, aValueName, nullptr, RRF_RT_REG_SZ,
+                                  nullptr, nullptr, &len);
+
+  mozilla::UniquePtr<uint8_t[]> buf = mozilla::MakeUnique<uint8_t[]>(len);
+  status = ::RegGetValueW(mKey, aValueName, nullptr, RRF_RT_REG_SZ, nullptr,
+                          buf.get(), &len);
+  if (status != ERROR_SUCCESS) {
+    return L"";
+  }
+
+  return reinterpret_cast<wchar_t*>(buf.get());
+}
+
+ComRegisterer::ComRegisterer(const GUID& aClsId, const wchar_t* aFriendlyName)
+    : mClassRoot(HKEY_CURRENT_USER, L"Software\\Classes"),
+      mFriendlyName(aFriendlyName) {
+  wchar_t guidStr[64];
+  HRESULT hr = ::StringCbPrintfW(
+      guidStr, sizeof(guidStr),
+      L"{%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x}", aClsId.Data1,
+      aClsId.Data2, aClsId.Data3, aClsId.Data4[0], aClsId.Data4[1],
+      aClsId.Data4[2], aClsId.Data4[3], aClsId.Data4[4], aClsId.Data4[5],
+      aClsId.Data4[6], aClsId.Data4[7]);
+  if (FAILED(hr)) {
+    return;
+  }
+
+  mClsId = guidStr;
+}
+
+bool ComRegisterer::UnregisterAll() {
+  bool isOk = true;
+  LSTATUS ls;
+
+  for (const wchar_t* subkey : kExtensionSubkeys) {
+    RegKey root(mClassRoot, subkey);
+
+    std::wstring currentHandler = root.GetString(nullptr);
+    if (currentHandler != mClsId) {
+      // If another extension is registered, don't overwrite it.
+      continue;
+    }
+
+    // Set an empty string instead of deleting the key.
+    if (!root.SetString(nullptr)) {
+      isOk = false;
+    }
+  }
+
+  std::wstring subkey(kClsIdPrefix);
+  subkey += mClsId;
+  ls = ::RegDeleteTreeW(mClassRoot, subkey.c_str());
+  if (ls != ERROR_SUCCESS && ls != ERROR_FILE_NOT_FOUND) {
+    isOk = false;
+  }
+
+  return isOk;
+}
+
+bool ComRegisterer::RegisterObject(const wchar_t* aThreadModel) {
+  std::wstring subkey(kClsIdPrefix);
+  subkey += mClsId;
+
+  RegKey root(mClassRoot, subkey.c_str());
+  if (!root || !root.SetString(nullptr, mFriendlyName)) {
+    return false;
+  }
+
+  RegKey inproc(root, L"InprocServer32");
+  return inproc && inproc.SetString(nullptr, gDllPath) &&
+         inproc.SetString(L"ThreadingModel", aThreadModel);
+}
+
+bool ComRegisterer::RegisterExtensions() {
+  for (const wchar_t* subkey : kExtensionSubkeys) {
+    RegKey root(mClassRoot, subkey);
+    std::wstring currentHandler = root.GetString(nullptr);
+    if (!currentHandler.empty()) {
+      // If another extension is registered, don't overwrite it.
+      continue;
+    }
+
+    if (!root.SetString(nullptr, mClsId)) {
+      return false;
+    }
+  }
+
+  return true;
+}
diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/RegUtils.h b/toolkit/components/aboutthirdparty/tests/TestShellEx/RegUtils.h
new file mode 100644
index 0000000000..21a23fdf16
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/RegUtils.h
@@ -0,0 +1,52 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_TestShellEx_RegUtils_h
+#define mozilla_TestShellEx_RegUtils_h
+
+#include <windows.h>
+#include <string>
+
+class RegKey final {
+  HKEY mKey;
+
+  bool SetStringInternal(const wchar_t* aValueName, const wchar_t* aValueData,
+                         DWORD aValueDataLength);
+
+ public:
+  RegKey() : mKey(nullptr) {}
+  RegKey(HKEY root, const wchar_t* aSubkey);
+  ~RegKey();
+
+  RegKey(RegKey&& aOther) = delete;
+  RegKey& operator=(RegKey&& aOther) = delete;
+  RegKey(const RegKey&) = delete;
+  RegKey& operator=(const RegKey&) = delete;
+
+  explicit operator bool() const { return !!mKey; }
+  operator HKEY() const { return mKey; }
+
+  bool SetString(const wchar_t* aValueName,
+                 const wchar_t* aValueData = nullptr);
+  bool SetString(const wchar_t* aValueName, const std::wstring& aValueData);
+  std::wstring GetString(const wchar_t* aValueName);
+};
+
+class ComRegisterer final {
+  RegKey mClassRoot;
+  std::wstring mClsId;
+  std::wstring mFriendlyName;
+
+ public:
+  ComRegisterer(const GUID& aClsId, const wchar_t* aFriendlyName);
+  ~ComRegisterer() = default;
+
+  bool UnregisterAll();
+  bool RegisterObject(const wchar_t* aThreadModel);
+  bool RegisterExtensions();
+};
+
+#endif  // mozilla_TestShellEx_RegUtils_h
diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/Resource.h b/toolkit/components/aboutthirdparty/tests/TestShellEx/Resource.h
new file mode 100644
index 0000000000..fa037194d7
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/Resource.h
@@ -0,0 +1,12 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_TestShellEx_Resource_h
+#define mozilla_TestShellEx_Resource_h
+
+#define IDI_ICON1 100
+
+#endif  // mozilla_TestShellEx_Resource_h
diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.cpp b/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.cpp
new file mode 100644
index 0000000000..dc0588483f
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.cpp
@@ -0,0 +1,68 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/RefPtr.h"
+#include "RegUtils.h"
+
+#include <windows.h>
+#include <objbase.h>
+
+already_AddRefed<IClassFactory> CreateFactory();
+
+// {10A9521E-0205-4CC7-93A1-62F30A9A54B3}
+GUID CLSID_TestShellEx = {
+    0x10a9521e, 0x205, 0x4cc7, {0x93, 0xa1, 0x62, 0xf3, 0xa, 0x9a, 0x54, 0xb3}};
+wchar_t kFriendlyName[] = L"Minimum Shell Extension for Firefox testing";
+
+std::wstring gDllPath;
+
+BOOL APIENTRY DllMain(HMODULE aModule, DWORD aReason, LPVOID) {
+  wchar_t buf[MAX_PATH];
+  switch (aReason) {
+    case DLL_PROCESS_ATTACH:
+      if (!::GetModuleFileNameW(aModule, buf, ARRAYSIZE(buf))) {
+        return FALSE;
+      }
+      gDllPath = buf;
+      break;
+    case DLL_THREAD_ATTACH:
+    case DLL_THREAD_DETACH:
+    case DLL_PROCESS_DETACH:
+      break;
+  }
+  return TRUE;
+}
+
+STDAPI DllGetClassObject(REFCLSID aClsid, REFIID aIid, void** aResult) {
+  if (!IsEqualCLSID(aClsid, CLSID_TestShellEx) ||
+      !IsEqualCLSID(aIid, IID_IClassFactory)) {
+    return CLASS_E_CLASSNOTAVAILABLE;
+  }
+
+  RefPtr<IClassFactory> factory = CreateFactory();
+  return factory ? factory->QueryInterface(aIid, aResult) : E_OUTOFMEMORY;
+}
+
+STDAPI DllCanUnloadNow() { return S_OK; }
+
+// These functions enable us to run "regsvr32 [/u] TestShellEx.dll" manually.
+// (No admin privilege is needed because all access is under HKCU.)
+// We don't use these functions in the mochitest, but having these makes easier
+// to test the module manually.
+STDAPI DllRegisterServer() {
+  ComRegisterer reg(CLSID_TestShellEx, kFriendlyName);
+  if (!reg.RegisterObject(L"Apartment") || !reg.RegisterExtensions()) {
+    return E_ACCESSDENIED;
+  }
+  return S_OK;
+}
+STDAPI DllUnregisterServer() {
+  ComRegisterer reg(CLSID_TestShellEx, kFriendlyName);
+  if (!reg.UnregisterAll()) {
+    return E_ACCESSDENIED;
+  }
+  return S_OK;
+}
diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.def b/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.def
new file mode 100644
index 0000000000..e83041771d
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.def
@@ -0,0 +1,10 @@
+;+# This Source Code Form is subject to the terms of the Mozilla Public

+;+# License, v. 2.0. If a copy of the MPL was not distributed with this

+;+# file, You can obtain one at http://mozilla.org/MPL/2.0/.

+

+LIBRARY TestShellEx

+EXPORTS

+  DllGetClassObject   PRIVATE

+  DllCanUnloadNow     PRIVATE

+  DllRegisterServer   PRIVATE

+  DllUnregisterServer PRIVATE

diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.rc b/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.rc
new file mode 100644
index 0000000000..7500551f02
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/TestShellEx.rc
@@ -0,0 +1,39 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public

+ * License, v. 2.0. If a copy of the MPL was not distributed with this

+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

+

+#include <winres.h>

+

+#include "Resource.h"

+

+IDI_ICON1 ICON DISCARDABLE "dinosaur.ico"

+

+VS_VERSION_INFO VERSIONINFO

+  FILEVERSION    1,2,3,4  // This field will be collected

+  PRODUCTVERSION 5,6,7,8

+  FILEFLAGSMASK 0x3fL

+#ifdef _DEBUG

+  FILEFLAGS 0x1L

+#else

+  FILEFLAGS 0x0L

+#endif

+  FILEOS VOS__WINDOWS32

+  FILETYPE VFT_DLL

+  FILESUBTYPE 0x0L

+

+BEGIN

+  BLOCK "StringFileInfo"

+  BEGIN

+    BLOCK "040904e4"

+    BEGIN

+      VALUE "CompanyName", "Mozilla Corporation"

+      VALUE "OriginalFilename", "TestShellEx.dll"

+      VALUE "ProductName", "Sample Shell Extension"

+    END

+  END

+

+  BLOCK "VarFileInfo"

+  BEGIN

+    VALUE "Translation", 0x0409, 1252

+  END

+END

diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/dinosaur.ico b/toolkit/components/aboutthirdparty/tests/TestShellEx/dinosaur.ico
new file mode 100644
index 0000000000..d44438903b
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/dinosaur.ico
diff --git a/toolkit/components/aboutthirdparty/tests/TestShellEx/moz.build b/toolkit/components/aboutthirdparty/tests/TestShellEx/moz.build
new file mode 100644
index 0000000000..44344a0e2e
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/TestShellEx/moz.build
@@ -0,0 +1,33 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+DIST_INSTALL = False
+
+SharedLibrary("TestShellEx")
+
+UNIFIED_SOURCES = [
+    "Factory.cpp",
+    "Icon.cpp",
+    "RegUtils.cpp",
+    "TestShellEx.cpp",
+]
+
+RCFILE = "TestShellEx.rc"
+DEFFILE = "TestShellEx.def"
+USE_LIBS += [
+    "mozglue",
+]
+
+if CONFIG["OS_ARCH"] == "WINNT":
+    OS_LIBS += [
+        "advapi32",
+        "uuid",
+    ]
+
+if CONFIG["COMPILE_ENVIRONMENT"]:
+    shared_library = "!%sTestShellEx%s" % (CONFIG["DLL_PREFIX"], CONFIG["DLL_SUFFIX"])
+    TEST_HARNESS_FILES.testing.mochitest.browser.toolkit.components.aboutthirdparty.tests.browser += [
+        shared_library
+    ]
diff --git a/toolkit/components/aboutthirdparty/tests/browser/browser.toml b/toolkit/components/aboutthirdparty/tests/browser/browser.toml
new file mode 100644
index 0000000000..8a2d9db429
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/browser/browser.toml
@@ -0,0 +1,6 @@
+[DEFAULT]
+head = "head.js"
+
+["browser_aboutthirdparty.js"]
+support-files = ["hello.zzz"]
+skip-if = ["os == 'win'"] # Bug 1776048
diff --git a/toolkit/components/aboutthirdparty/tests/browser/browser_aboutthirdparty.js b/toolkit/components/aboutthirdparty/tests/browser/browser_aboutthirdparty.js
new file mode 100644
index 0000000000..0a53823a35
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/browser/browser_aboutthirdparty.js
@@ -0,0 +1,317 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Return card containers matching a given name
+function getCardsByName(aContainer, aLeafName) {
+  const matchedCards = [];
+  const allCards = aContainer.querySelectorAll(".card");
+  for (const card of allCards) {
+    const nameLabel = card.querySelector(".module-name");
+    if (nameLabel.textContent == aLeafName) {
+      matchedCards.push(card);
+    }
+  }
+  return matchedCards;
+}
+
+function getDetailRow(aContainer, aLabel) {
+  return aContainer.querySelector(`[data-l10n-id=${aLabel}]`).parentElement;
+}
+
+function verifyClipboardData(aModuleJson) {
+  Assert.ok(
+    aModuleJson.hasOwnProperty("blocked"),
+    "Clipboard data should have blocked property."
+  );
+  const blocked = aModuleJson.blocked.filter(
+    x => x.name == kUserBlockedModuleName
+  );
+  Assert.equal(
+    blocked.length,
+    1,
+    "Blocked array should contain the blocked module one time."
+  );
+  Assert.ok(
+    aModuleJson.hasOwnProperty("modules"),
+    "Clipboard data should have modules property"
+  );
+  let aModuleArray = aModuleJson.modules;
+  const filtered = aModuleArray.filter(x => x.name == kExtensionModuleName);
+  Assert.equal(filtered.length, 1, "No duplicate data for the module.");
+
+  const kDeletedPropertiesOfModule = [
+    "application",
+    "dllFile",
+    "loadingOnMain",
+    "trustFlags",
+  ];
+  const kDeletedPropertiesOfLoadingEvent = [
+    "baseAddress",
+    "isDependent",
+    "mainThread",
+    "moduleIndex",
+    "processUptimeMS",
+  ];
+
+  for (const module of aModuleArray) {
+    for (const deletedProperty of kDeletedPropertiesOfModule) {
+      Assert.ok(
+        !module.hasOwnProperty(deletedProperty),
+        `The property \`${deletedProperty}\` is deleted.`
+      );
+    }
+
+    Assert.ok(
+      !module.hasOwnProperty("typeFlags") || module.typeFlags != 0,
+      "typeFlags does not exist or is non-zero."
+    );
+
+    for (const event of module.events) {
+      for (const deletedProperty of kDeletedPropertiesOfLoadingEvent) {
+        Assert.ok(
+          !event.hasOwnProperty(deletedProperty),
+          `The property \`${deletedProperty}\` is deleted.`
+        );
+      }
+    }
+  }
+}
+
+function verifyModuleSorting(compareFunc) {
+  const uninteresting = {
+    typeFlags: 0,
+    isCrasher: false,
+    loadingOnMain: 0,
+  };
+  const crasherNotBlocked = { ...uninteresting, isCrasher: true };
+  const crasherBlocked = {
+    ...uninteresting,
+    isCrasher: true,
+    typeFlags: Ci.nsIAboutThirdParty.ModuleType_BlockedByUserAtLaunch,
+  };
+  const justBlocked = {
+    ...uninteresting,
+    typeFlags: Ci.nsIAboutThirdParty.ModuleType_BlockedByUserAtLaunch,
+  };
+  const uninterestingButSlow = {
+    ...uninteresting,
+    loadingOnMain: 10,
+  };
+  let modules = [
+    uninteresting,
+    uninterestingButSlow,
+    crasherNotBlocked,
+    justBlocked,
+    crasherBlocked,
+  ];
+  modules.sort(compareFunc);
+  Assert.equal(
+    JSON.stringify([
+      crasherBlocked,
+      justBlocked,
+      crasherNotBlocked,
+      uninterestingButSlow,
+      uninteresting,
+    ]),
+    JSON.stringify(modules),
+    "Modules sort in expected order"
+  );
+}
+
+add_task(async () => {
+  registerCleanupFunction(() => {
+    unregisterAll();
+  });
+  await registerObject();
+  registerExtensions();
+  loadShellExtension();
+
+  await kATP.collectSystemInfo();
+  Assert.equal(
+    kATP.lookupModuleType(kExtensionModuleName),
+    Ci.nsIAboutThirdParty.ModuleType_ShellExtension,
+    "lookupModuleType() returns a correct type " +
+      "after system info was collected."
+  );
+
+  await BrowserTestUtils.withNewTab("about:third-party", async browser => {
+    if (!content.fetchDataDone) {
+      const mainDiv = content.document.getElementById("main");
+      await BrowserTestUtils.waitForMutationCondition(
+        mainDiv,
+        { childList: true },
+        () => mainDiv.childElementCount > 0
+      );
+      Assert.ok(content.fetchDataDone, "onLoad() is completed.");
+    }
+
+    const reload = content.document.getElementById("button-reload");
+    if (!reload.hidden) {
+      reload.click();
+      await BrowserTestUtils.waitForMutationCondition(
+        reload,
+        { attributes: true, attributeFilter: ["hidden"] },
+        () => reload.hidden
+      );
+    }
+
+    Assert.ok(
+      content.document.getElementById("no-data").hidden,
+      "The no-data message is hidden."
+    );
+    const blockedCards = getCardsByName(
+      content.document,
+      kUserBlockedModuleName
+    );
+    Assert.equal(
+      blockedCards.length,
+      1,
+      "Only one card matching the blocked module exists."
+    );
+    const blockedCard = blockedCards[0];
+    Assert.equal(
+      blockedCard.querySelectorAll(".button-block.module-blocked").length,
+      1,
+      "The blocked module has a button indicating it is blocked"
+    );
+    let blockedBlockButton = blockedCard.querySelector(
+      ".button-block.module-blocked"
+    );
+    Assert.equal(
+      blockedBlockButton.getAttribute("data-l10n-id"),
+      "third-party-button-to-unblock-module",
+      "Button to block the module has correct title"
+    );
+    blockedBlockButton.click();
+    await BrowserTestUtils.promiseAlertDialogOpen("cancel");
+    Assert.ok(
+      !blockedBlockButton.classList.contains("module-blocked"),
+      "After clicking to unblock a module, button should not have module-blocked class."
+    );
+    Assert.equal(
+      blockedBlockButton.getAttribute("data-l10n-id"),
+      "third-party-button-to-block-module",
+      "After clicking to unblock a module, button should have correct title."
+    );
+    // Restore this to blocked for later tests
+    blockedBlockButton.click();
+    await BrowserTestUtils.promiseAlertDialogOpen("cancel");
+    Assert.ok(
+      blockedBlockButton.classList.contains("module-blocked"),
+      "After clicking to block a module, button should have module-blocked class."
+    );
+    Assert.equal(
+      blockedBlockButton.getAttribute("data-l10n-id"),
+      "third-party-button-to-unblock-module",
+      "After clicking to block a module, button should have correct title."
+    );
+
+    const cards = getCardsByName(content.document, kExtensionModuleName);
+    Assert.equal(cards.length, 1, "Only one card matching the module exists.");
+    const card = cards[0];
+
+    const blockButton = card.querySelector(".button-block");
+    Assert.ok(
+      !blockButton.classList.contains("blocklist-disabled"),
+      "Button to block the module does not indicate the blocklist is disabled."
+    );
+    Assert.ok(
+      !blockButton.classList.contains("module-blocked"),
+      "Button to block the module does not indicate the module is blocked."
+    );
+
+    Assert.ok(
+      card.querySelector(".image-warning").hidden,
+      "No warning sign for the module."
+    );
+    Assert.equal(
+      card.querySelector(".image-unsigned").hidden,
+      false,
+      "The module is labeled as unsigned."
+    );
+    Assert.equal(
+      card.querySelector(".tag-shellex").hidden,
+      false,
+      "The module is labeled as a shell extension."
+    );
+    Assert.equal(
+      card.querySelector(".tag-ime").hidden,
+      true,
+      "The module is not labeled as an IME."
+    );
+
+    const versionRow = getDetailRow(card, "third-party-detail-version");
+    Assert.equal(
+      versionRow.childNodes[1].textContent,
+      "1.2.3.4",
+      "The version matches a value in TestShellEx.rc."
+    );
+    const vendorRow = getDetailRow(card, "third-party-detail-vendor");
+    Assert.equal(
+      vendorRow.childNodes[1].textContent,
+      "Mozilla Corporation",
+      "The vendor name matches a value in TestShellEx.rc."
+    );
+    const occurrencesRow = getDetailRow(card, "third-party-detail-occurrences");
+    Assert.equal(
+      Number(occurrencesRow.childNodes[1].textContent),
+      1,
+      "The module was loaded once."
+    );
+    const durationRow = getDetailRow(card, "third-party-detail-duration");
+    Assert.ok(
+      Number(durationRow.childNodes[1].textContent),
+      "The duration row shows a valid number."
+    );
+
+    const eventTable = card.querySelector(".event-table");
+    const tableCells = eventTable.querySelectorAll("td");
+    Assert.equal(
+      tableCells.length,
+      3,
+      "The table has three cells as there is only one event."
+    );
+    Assert.equal(
+      tableCells[0].querySelector(".process-type").getAttribute("data-l10n-id"),
+      "process-type-default",
+      "The module was loaded into the main process."
+    );
+    Assert.ok(
+      Number(tableCells[0].querySelector(".process-id").textContent),
+      "A valid process ID is displayed."
+    );
+    Assert.equal(
+      tableCells[1].querySelector(".event-duration").textContent,
+      durationRow.childNodes[1].textContent,
+      "The event's duration is the same as the average " +
+        "as there is only one event."
+    );
+    Assert.equal(
+      tableCells[1].querySelector(".tag-background").hidden,
+      true,
+      "The icon handler is loaded in the main thread."
+    );
+    Assert.equal(
+      tableCells[2].getAttribute("data-l10n-id"),
+      "third-party-status-loaded",
+      "The module was really loaded without being blocked."
+    );
+
+    const button = content.document.getElementById("button-copy-to-clipboard");
+    button.click();
+
+    // Wait until copying is done and the button becomes clickable.
+    await BrowserTestUtils.waitForMutationCondition(
+      button,
+      { attributes: true },
+      () => !button.disabled
+    );
+
+    const copiedJSON = JSON.parse(await navigator.clipboard.readText());
+    Assert.ok(copiedJSON instanceof Object, "Data is an object.");
+    verifyClipboardData(copiedJSON);
+
+    verifyModuleSorting(content.moduleCompareForDisplay);
+  });
+});
diff --git a/toolkit/components/aboutthirdparty/tests/browser/head.js b/toolkit/components/aboutthirdparty/tests/browser/head.js
new file mode 100644
index 0000000000..eba3948046
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/browser/head.js
@@ -0,0 +1,144 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const kClsidTestShellEx = "{10a9521e-0205-4cc7-93a1-62f30a9a54b3}";
+const kFriendlyName = "Minimum Shell Extension for Firefox testing";
+const kExtensionSubkeys = [".zzz\\shellex\\IconHandler"];
+const kExtensionModuleName = "TestShellEx.dll";
+const kUserBlockedModuleName = "TestDllBlocklist_UserBlocked.dll";
+const kFileFilterInDialog = "*.zzz";
+const kATP = Cc["@mozilla.org/about-thirdparty;1"].getService(
+  Ci.nsIAboutThirdParty
+);
+
+function loadShellExtension() {
+  // This method call opens the file dialog and shows the support file
+  // "hello.zzz" in it, which loads TestShellEx.dll to show an icon
+  // for files with the .zzz extension.
+  kATP.openAndCloseFileDialogForTesting(
+    kExtensionModuleName,
+    getTestFilePath(""),
+    kFileFilterInDialog
+  );
+}
+
+async function registerObject() {
+  const reg = Cc["@mozilla.org/windows-registry-key;1"].createInstance(
+    Ci.nsIWindowsRegKey
+  );
+
+  reg.create(
+    Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER,
+    "Software\\Classes\\CLSID\\" + kClsidTestShellEx,
+    Ci.nsIWindowsRegKey.ACCESS_ALL
+  );
+
+  reg.writeStringValue("", kFriendlyName);
+
+  const inprocServer = reg.createChild(
+    "InprocServer32",
+    Ci.nsIWindowsRegKey.ACCESS_ALL
+  );
+
+  const moduleFullPath = getTestFilePath(kExtensionModuleName);
+  Assert.ok(await IOUtils.exists(moduleFullPath), "The module file exists.");
+
+  inprocServer.writeStringValue("", moduleFullPath);
+  inprocServer.writeStringValue("ThreadingModel", "Apartment");
+  reg.close();
+
+  info("registerObject() done - " + moduleFullPath);
+}
+
+function registerExtensions() {
+  for (const subkey of kExtensionSubkeys) {
+    const reg = Cc["@mozilla.org/windows-registry-key;1"].createInstance(
+      Ci.nsIWindowsRegKey
+    );
+    reg.create(
+      Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER,
+      "Software\\Classes\\" + subkey,
+      Ci.nsIWindowsRegKey.ACCESS_ALL
+    );
+
+    let currentExtension = "";
+    try {
+      // If the key was just created above, the default value does not exist,
+      // so readStringValue will throw NS_ERROR_FAILURE.
+      currentExtension = reg.readStringValue("");
+    } catch (e) {}
+
+    try {
+      if (!currentExtension) {
+        reg.writeStringValue("", kClsidTestShellEx);
+      } else if (currentExtension != kClsidTestShellEx) {
+        throw new Error(
+          `Another extension \`${currentExtension}\` has been registered.`
+        );
+      }
+    } catch (e) {
+      throw new Error("Failed to register TestShellEx.dll: " + e);
+    } finally {
+      reg.close();
+    }
+  }
+}
+
+function unregisterAll() {
+  for (const subkey of kExtensionSubkeys) {
+    const reg = Cc["@mozilla.org/windows-registry-key;1"].createInstance(
+      Ci.nsIWindowsRegKey
+    );
+
+    try {
+      reg.open(
+        Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER,
+        "Software\\Classes\\" + subkey,
+        Ci.nsIWindowsRegKey.ACCESS_ALL
+      );
+
+      if (reg.readStringValue("") != kClsidTestShellEx) {
+        // If another extension is registered, don't overwrite it.
+        continue;
+      }
+
+      // Set an empty string instead of deleting the key
+      // not to touch non-default values.
+      reg.writeStringValue("", "");
+    } catch (e) {
+      info(`Failed to unregister \`${subkey}\`: ` + e);
+    } finally {
+      reg.close();
+    }
+  }
+
+  const reg = Cc["@mozilla.org/windows-registry-key;1"].createInstance(
+    Ci.nsIWindowsRegKey
+  );
+  reg.open(
+    Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER,
+    "Software\\Classes\\CLSID",
+    Ci.nsIWindowsRegKey.ACCESS_ALL
+  );
+
+  try {
+    const child = reg.openChild(
+      kClsidTestShellEx,
+      Ci.nsIWindowsRegKey.ACCESS_ALL
+    );
+    try {
+      child.removeChild("InprocServer32");
+    } catch (e) {
+    } finally {
+      child.close();
+    }
+
+    reg.removeChild(kClsidTestShellEx);
+  } catch (e) {
+  } finally {
+    reg.close();
+  }
+}
diff --git a/toolkit/components/aboutthirdparty/tests/browser/hello.zzz b/toolkit/components/aboutthirdparty/tests/browser/hello.zzz
new file mode 100644
index 0000000000..e69ab604b3
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/browser/hello.zzz
@@ -0,0 +1 @@
+Showing this file on Windows Shell loads TestShellEx.dll.

diff --git a/toolkit/components/aboutthirdparty/tests/gtest/TestAboutThirdParty.cpp b/toolkit/components/aboutthirdparty/tests/gtest/TestAboutThirdParty.cpp
new file mode 100644
index 0000000000..565e87e0f1
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/gtest/TestAboutThirdParty.cpp
@@ -0,0 +1,125 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#include <windows.h>
+#include "gtest/gtest.h"
+
+#include "../../AboutThirdPartyUtils.h"
+#include "mozilla/AboutThirdParty.h"
+#include "mozilla/ArrayUtils.h"
+#include "nsTArray.h"
+
+using namespace mozilla;
+
+#define WEATHER_RU u"\x041F\x043E\x0433\x043E\x0434\x0430"_ns
+#define WEATHER_JA u"\x5929\x6C17"_ns
+
+TEST(AboutThirdParty, CompareIgnoreCase)
+{
+  EXPECT_EQ(CompareIgnoreCase(u""_ns, u""_ns), 0);
+  EXPECT_EQ(CompareIgnoreCase(u"abc"_ns, u"aBc"_ns), 0);
+  EXPECT_LT(CompareIgnoreCase(u"a"_ns, u"ab"_ns), 0);
+  EXPECT_GT(CompareIgnoreCase(u"ab"_ns, u"A"_ns), 0);
+  EXPECT_LT(CompareIgnoreCase(u""_ns, u"aB"_ns), 0);
+  EXPECT_GT(CompareIgnoreCase(u"ab"_ns, u""_ns), 0);
+
+  // non-ascii testcases
+  EXPECT_EQ(CompareIgnoreCase(WEATHER_JA, WEATHER_JA), 0);
+  EXPECT_EQ(CompareIgnoreCase(WEATHER_RU, WEATHER_RU), 0);
+  EXPECT_LT(CompareIgnoreCase(WEATHER_RU, WEATHER_JA), 0);
+  EXPECT_GT(CompareIgnoreCase(WEATHER_JA, WEATHER_RU), 0);
+  EXPECT_EQ(CompareIgnoreCase(WEATHER_RU u"x"_ns WEATHER_JA,
+                              WEATHER_RU u"X"_ns WEATHER_JA),
+            0);
+  EXPECT_GT(
+      CompareIgnoreCase(WEATHER_RU u"a"_ns WEATHER_JA, WEATHER_RU u"A"_ns), 0);
+  EXPECT_LT(CompareIgnoreCase(WEATHER_RU u"a"_ns WEATHER_RU,
+                              WEATHER_RU u"A"_ns WEATHER_JA),
+            0);
+}
+
+TEST(AboutThirdParty, MsiPackGuid)
+{
+  nsAutoString packedGuid;
+  EXPECT_FALSE(
+      MsiPackGuid(u"EDA620E3-AA98-3846-B81E-3493CB2E0E02"_ns, packedGuid));
+  EXPECT_FALSE(
+      MsiPackGuid(u"*EDA620E3-AA98-3846-B81E-3493CB2E0E02*"_ns, packedGuid));
+  EXPECT_TRUE(
+      MsiPackGuid(u"{EDA620E3-AA98-3846-B81E-3493CB2E0E02}"_ns, packedGuid));
+  EXPECT_STREQ(packedGuid.get(), L"3E026ADE89AA64838BE14339BCE2E020");
+}
+
+TEST(AboutThirdParty, CorrectMsiComponentPath)
+{
+  nsAutoString testPath;
+
+  testPath = u""_ns;
+  EXPECT_FALSE(CorrectMsiComponentPath(testPath));
+
+  testPath = u"\\\\server\\share"_ns;
+  EXPECT_FALSE(CorrectMsiComponentPath(testPath));
+
+  testPath = u"hello"_ns;
+  EXPECT_FALSE(CorrectMsiComponentPath(testPath));
+
+  testPath = u"02:\\Software"_ns;
+  EXPECT_FALSE(CorrectMsiComponentPath(testPath));
+
+  testPath = u"C:\\path\\"_ns;
+  EXPECT_TRUE(CorrectMsiComponentPath(testPath));
+  EXPECT_STREQ(testPath.get(), L"C:\\path\\");
+
+  testPath = u"C?\\path\\"_ns;
+  EXPECT_TRUE(CorrectMsiComponentPath(testPath));
+  EXPECT_STREQ(testPath.get(), L"C:\\path\\");
+
+  testPath = u"C:\\?path\\"_ns;
+  EXPECT_TRUE(CorrectMsiComponentPath(testPath));
+  EXPECT_STREQ(testPath.get(), L"C:\\path\\");
+
+  testPath = u"\\?path\\"_ns;
+  EXPECT_FALSE(CorrectMsiComponentPath(testPath));
+}
+
+TEST(AboutThirdParty, InstallLocations)
+{
+  const nsLiteralString kDirectoriesUnsorted[] = {
+      u"C:\\duplicate\\"_ns, u"C:\\duplicate\\"_ns, u"C:\\app1\\"_ns,
+      u"C:\\app2\\"_ns,      u"C:\\app11\\"_ns,     u"C:\\app12\\"_ns,
+  };
+
+  struct TestCase {
+    nsLiteralString mFile;
+    nsLiteralString mInstallPath;
+  } const kTestCases[] = {
+      {u"C:\\app\\sub\\file.dll"_ns, u""_ns},
+      {u"C:\\app1\\sub\\file.dll"_ns, u"C:\\app1\\"_ns},
+      {u"C:\\app11\\sub\\file.dll"_ns, u"C:\\app11\\"_ns},
+      {u"C:\\app12\\sub\\file.dll"_ns, u"C:\\app12\\"_ns},
+      {u"C:\\app13\\sub\\file.dll"_ns, u""_ns},
+      {u"C:\\duplicate\\sub\\file.dll"_ns, u""_ns},
+  };
+
+  nsTArray<InstallLocationT> locations(ArrayLength(kDirectoriesUnsorted));
+  for (size_t i = 0; i < ArrayLength(kDirectoriesUnsorted); ++i) {
+    locations.EmplaceBack(kDirectoriesUnsorted[i], new InstalledApplication());
+  }
+
+  locations.Sort([](const InstallLocationT& aA, const InstallLocationT& aB) {
+    return CompareIgnoreCase(aA.first(), aB.first());
+  });
+
+  for (const auto& testCase : kTestCases) {
+    auto bounds = EqualRange(locations, 0, locations.Length(),
+                             InstallLocationComparator(testCase.mFile));
+    if (bounds.second - bounds.first != 1) {
+      EXPECT_TRUE(testCase.mInstallPath.IsEmpty());
+      continue;
+    }
+
+    EXPECT_EQ(locations[bounds.first].first(), testCase.mInstallPath);
+  }
+}
diff --git a/toolkit/components/aboutthirdparty/tests/gtest/moz.build b/toolkit/components/aboutthirdparty/tests/gtest/moz.build
new file mode 100644
index 0000000000..659c0836db
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/gtest/moz.build
@@ -0,0 +1,13 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+LOCAL_INCLUDES += [
+    "../..",
+]
+
+UNIFIED_SOURCES += ["TestAboutThirdParty.cpp"]
+
+FINAL_LIBRARY = "xul-gtest"
diff --git a/toolkit/components/aboutthirdparty/tests/xpcshell/head.js b/toolkit/components/aboutthirdparty/tests/xpcshell/head.js
new file mode 100644
index 0000000000..ede1d3cc73
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/xpcshell/head.js
@@ -0,0 +1,10 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const kExtensionModuleName = "TestShellEx.dll";
+const kATP = Cc["@mozilla.org/about-thirdparty;1"].getService(
+  Ci.nsIAboutThirdParty
+);
diff --git a/toolkit/components/aboutthirdparty/tests/xpcshell/test_aboutthirdparty.js b/toolkit/components/aboutthirdparty/tests/xpcshell/test_aboutthirdparty.js
new file mode 100644
index 0000000000..281fe42188
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/xpcshell/test_aboutthirdparty.js
@@ -0,0 +1,65 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+add_task(async () => {
+  Assert.equal(
+    kATP.lookupModuleType(kExtensionModuleName),
+    0,
+    "lookupModuleType() returns 0 before system info is collected."
+  );
+
+  // Make sure successive calls of collectSystemInfo() do not
+  // cause anything bad.
+  const kLoopCount = 100;
+  const promises = [];
+  for (let i = 0; i < kLoopCount; ++i) {
+    promises.push(kATP.collectSystemInfo());
+  }
+
+  const collectSystemInfoResults = await Promise.allSettled(promises);
+  Assert.equal(collectSystemInfoResults.length, kLoopCount);
+
+  for (const result of collectSystemInfoResults) {
+    Assert.ok(
+      result.status == "fulfilled",
+      "All results from collectSystemInfo() are resolved."
+    );
+  }
+
+  Assert.equal(
+    kATP.lookupModuleType("SHELL32.dll"),
+    Ci.nsIAboutThirdParty.ModuleType_ShellExtension,
+    "Shell32.dll is always registered as a shell extension."
+  );
+
+  Assert.equal(
+    kATP.lookupModuleType(""),
+    Ci.nsIAboutThirdParty.ModuleType_Unknown,
+    "Looking up an empty string succeeds and returns ModuleType_Unknown."
+  );
+
+  Assert.equal(
+    kATP.lookupModuleType(null),
+    Ci.nsIAboutThirdParty.ModuleType_Unknown,
+    "Looking up null succeeds and returns ModuleType_Unknown."
+  );
+
+  Assert.equal(
+    kATP.lookupModuleType("invalid name"),
+    Ci.nsIAboutThirdParty.ModuleType_Unknown,
+    "Looking up an invalid name succeeds and returns ModuleType_Unknown."
+  );
+
+  Assert.equal(
+    kATP.lookupApplication(""),
+    null,
+    "Looking up an empty string returns null."
+  );
+
+  Assert.equal(
+    kATP.lookupApplication("invalid path"),
+    null,
+    "Looking up an invalid path returns null."
+  );
+});
diff --git a/toolkit/components/aboutthirdparty/tests/xpcshell/xpcshell.toml b/toolkit/components/aboutthirdparty/tests/xpcshell/xpcshell.toml
new file mode 100644
index 0000000000..46a2fbc2ff
--- /dev/null
+++ b/toolkit/components/aboutthirdparty/tests/xpcshell/xpcshell.toml
@@ -0,0 +1,4 @@
+[DEFAULT]
+head = "head.js"
+
+["test_aboutthirdparty.js"]