Adding upstream version 115.7.0esr.upstream/115.7.0esr

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

16 files changed, 2682 insertions, 0 deletions

diff --git a/browser/components/translations/tests/browser/browser.ini b/browser/components/translations/tests/browser/browser.ini
new file mode 100644
index 0000000000..fd67597972
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser.ini
@@ -0,0 +1,19 @@
+[DEFAULT]
+support-files =
+  head.js
+  !/toolkit/components/translations/tests/browser/shared-head.js
+  !/toolkit/components/translations/tests/browser/translations-test.mjs
+[browser_manage_languages.js]
+[browser_translations_panel_always_translate_language.js]
+[browser_translations_panel_basics.js]
+[browser_translations_panel_beta_langs.js]
+[browser_translations_panel_button.js]
+[browser_translations_panel_cancel.js]
+[browser_translations_panel_gear.js]
+[browser_translations_panel_never_translate_language.js]
+[browser_translations_panel_never_translate_site.js]
+[browser_translations_panel_retry.js]
+[browser_translations_panel_switch_languages.js]
+[browser_translations_telemetry_open_panel.js]
+[browser_translations_telemetry_translation_failure.js]
+[browser_translations_telemetry_translation_request.js]
diff --git a/browser/components/translations/tests/browser/browser_manage_languages.js b/browser/components/translations/tests/browser/browser_manage_languages.js
new file mode 100644
index 0000000000..651029ad86
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_manage_languages.js
@@ -0,0 +1,195 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const frenchModels = [
+  "lex.50.50.enfr.s2t.bin",
+  "lex.50.50.fren.s2t.bin",
+  "model.enfr.intgemm.alphas.bin",
+  "model.fren.intgemm.alphas.bin",
+  "vocab.enfr.spm",
+  "vocab.fren.spm",
+];
+
+add_task(async function test_about_preferences_manage_languages() {
+  const {
+    cleanup,
+    remoteClients,
+    elements: {
+      downloadAllLabel,
+      downloadAll,
+      deleteAll,
+      frenchLabel,
+      frenchDownload,
+      frenchDelete,
+      spanishLabel,
+      spanishDownload,
+      spanishDelete,
+    },
+  } = await setupAboutPreferences([
+    { fromLang: "en", toLang: "fr" },
+    { fromLang: "fr", toLang: "en" },
+    { fromLang: "en", toLang: "es" },
+    { fromLang: "es", toLang: "en" },
+  ]);
+
+  is(
+    downloadAllLabel.getAttribute("data-l10n-id"),
+    "translations-manage-all-language",
+    "The first row is all of the languages."
+  );
+  is(frenchLabel.textContent, "French", "There is a French row.");
+  is(spanishLabel.textContent, "Spanish", "There is a Spanish row.");
+
+  await assertVisibility({
+    message: "Everything starts out as available to download",
+    visible: { downloadAll, frenchDownload, spanishDownload },
+    hidden: { deleteAll, frenchDelete, spanishDelete },
+  });
+
+  click(frenchDownload, "Downloading French");
+
+  Assert.deepEqual(
+    await remoteClients.translationModels.resolvePendingDownloads(
+      frenchModels.length
+    ),
+    frenchModels,
+    "French models were downloaded."
+  );
+
+  await assertVisibility({
+    message: "French can now be deleted, and delete all is available.",
+    visible: { downloadAll, deleteAll, frenchDelete, spanishDownload },
+    hidden: { frenchDownload, spanishDelete },
+  });
+
+  click(frenchDelete, "Deleting French");
+
+  await assertVisibility({
+    message: "Everything can be downloaded.",
+    visible: { downloadAll, frenchDownload, spanishDownload },
+    hidden: { deleteAll, frenchDelete, spanishDelete },
+  });
+
+  click(downloadAll, "Downloading all languages.");
+
+  const allModels = [
+    "lex.50.50.enes.s2t.bin",
+    "lex.50.50.enfr.s2t.bin",
+    "lex.50.50.esen.s2t.bin",
+    "lex.50.50.fren.s2t.bin",
+    "model.enes.intgemm.alphas.bin",
+    "model.enfr.intgemm.alphas.bin",
+    "model.esen.intgemm.alphas.bin",
+    "model.fren.intgemm.alphas.bin",
+    "vocab.enes.spm",
+    "vocab.enfr.spm",
+    "vocab.esen.spm",
+    "vocab.fren.spm",
+  ];
+  Assert.deepEqual(
+    await remoteClients.translationModels.resolvePendingDownloads(
+      allModels.length
+    ),
+    allModels,
+    "All models were downloaded."
+  );
+  Assert.deepEqual(
+    await remoteClients.languageIdModels.resolvePendingDownloads(1),
+    ["lid.176.ftz"],
+    "Language ID model was downloaded."
+  );
+  Assert.deepEqual(
+    await remoteClients.translationsWasm.resolvePendingDownloads(2),
+    ["bergamot-translator", "fasttext-wasm"],
+    "Wasm was downloaded."
+  );
+
+  await assertVisibility({
+    message: "Everything can be deleted.",
+    visible: { deleteAll, frenchDelete, spanishDelete },
+    hidden: { downloadAll, frenchDownload, spanishDownload },
+  });
+
+  click(deleteAll, "Deleting all languages.");
+
+  await assertVisibility({
+    message: "Everything can be downloaded again",
+    visible: { downloadAll, frenchDownload, spanishDownload },
+    hidden: { deleteAll, frenchDelete, spanishDelete },
+  });
+
+  click(frenchDownload, "Downloading French.");
+  click(spanishDownload, "Downloading Spanish.");
+
+  Assert.deepEqual(
+    await remoteClients.translationModels.resolvePendingDownloads(
+      allModels.length
+    ),
+    allModels,
+    "All models were downloaded again."
+  );
+
+  remoteClients.translationsWasm.assertNoNewDownloads();
+  remoteClients.languageIdModels.assertNoNewDownloads();
+
+  await assertVisibility({
+    message: "Everything is downloaded again.",
+    visible: { deleteAll, frenchDelete, spanishDelete },
+    hidden: { downloadAll, frenchDownload, spanishDownload },
+  });
+
+  return cleanup();
+});
+
+add_task(async function test_about_preferences_download_reject() {
+  const {
+    cleanup,
+    remoteClients,
+    elements: { document, frenchDownload },
+  } = await setupAboutPreferences([
+    { fromLang: "en", toLang: "fr" },
+    { fromLang: "fr", toLang: "en" },
+    { fromLang: "en", toLang: "es" },
+    { fromLang: "es", toLang: "en" },
+  ]);
+
+  click(frenchDownload, "Downloading French");
+
+  is(
+    maybeGetByL10nId("translations-manage-error-download", document),
+    null,
+    "No error messages are present."
+  );
+
+  const errors = await captureTranslationsError(() =>
+    remoteClients.translationModels.rejectPendingDownloads(frenchModels.length)
+  );
+
+  ok(
+    !!errors.length,
+    `The errors for download should have been reported, found ${errors.length} errors`
+  );
+  for (const { error } of errors) {
+    is(
+      error?.message,
+      "Failed to download file.",
+      "The error reported was a download error."
+    );
+  }
+
+  await TestUtils.waitForCondition(
+    () => maybeGetByL10nId("translations-manage-error-download", document),
+    "The error message is now visible."
+  );
+
+  click(frenchDownload, "Attempting to download French again", document);
+  is(
+    maybeGetByL10nId("translations-manage-error-download", document),
+    null,
+    "The error message is hidden again."
+  );
+
+  return cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_always_translate_language.js b/browser/components/translations/tests/browser/browser_translations_panel_always_translate_language.js
new file mode 100644
index 0000000000..4bc2c7dc15
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_always_translate_language.js
@@ -0,0 +1,413 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests the effect of toggling the always-translate-language menuitem.
+ * Checking the box on an untranslated page should immediately translate the page.
+ * Unchecking the box on a translated page should immediately restore the page.
+ */
+add_task(async function test_toggle_always_translate_language_menuitem() {
+  const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+    prefs: [["browser.translations.alwaysTranslateLanguages", "pl,fr"]],
+  });
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: false, icon: true },
+    "The translations button is visible."
+  );
+
+  info(
+    'The document language "es" is not in the alwaysTranslateLanguages pref, ' +
+      "so the page should be untranslated, in its original form"
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  info(
+    "Simulate clicking always-translate-language in the settings menu, " +
+      "adding the document language to the alwaysTranslateLanguages pref"
+  );
+  await openSettingsMenu();
+
+  await assertIsAlwaysTranslateLanguage("es", false);
+  await toggleAlwaysTranslateLanguage();
+  await assertIsAlwaysTranslateLanguage("es", true);
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: true, locale: false, icon: true },
+    "The icon presents the loading indicator."
+  );
+
+  await resolveDownloads(1);
+
+  const { locale } = await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: true, icon: true },
+    "The icon presents the locale."
+  );
+
+  is(locale.innerText, "en", "The English language tag is shown.");
+
+  info(
+    "The page should now be automatically translated because the document language " +
+      "should be added to the always-translate pref"
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is translated automatically",
+      getH1,
+      "DON QUIJOTE DE LA MANCHA [es to en, html]"
+    );
+  });
+
+  info("Navigate to a different Spanish page");
+  await navigate(SPANISH_PAGE_URL_DOT_ORG);
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: true, locale: false, icon: true },
+    "The icon presents the loading indicator."
+  );
+
+  await resolveDownloads(1);
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: true, icon: true },
+    "The icon presents the locale."
+  );
+
+  is(locale.innerText, "en", "The English language tag is shown.");
+
+  info(
+    "The page should now be automatically translated because the document language " +
+      "should be added to the always-translate pref"
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is translated automatically",
+      getH1,
+      "DON QUIJOTE DE LA MANCHA [es to en, html]"
+    );
+  });
+
+  info(
+    "Simulate clicking always-translate-language in the settings menu " +
+      "removing the document language from the alwaysTranslateLanguages pref"
+  );
+  await openSettingsMenu();
+
+  await assertIsAlwaysTranslateLanguage("es", true);
+  await toggleAlwaysTranslateLanguage();
+  await assertIsAlwaysTranslateLanguage("es", false);
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: false, icon: true },
+    "Only the button appears"
+  );
+
+  info(
+    "The page should no longer automatically translated because the document language " +
+      "should be removed from the always-translate pref"
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await cleanup();
+});
+
+/**
+ * Tests the effect of toggling the always-translate-language menuitem after the page has
+ * been manually translated. This should not reload or retranslate the page, but just check
+ * the box.
+ */
+add_task(
+  async function test_activate_always_translate_language_after_manual_translation() {
+    const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+      page: SPANISH_PAGE_URL,
+      languagePairs: LANGUAGE_PAIRS,
+      prefs: [["browser.translations.alwaysTranslateLanguages", "pl,fr"]],
+    });
+
+    const { button } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The button is available."
+    );
+
+    info(
+      'The document language "es" is not in the alwaysTranslateLanguages pref, ' +
+        "so the page should be untranslated, in its original form"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await waitForTranslationsPopupEvent("popupshown", () => {
+      click(button, "Opening the popup");
+    });
+
+    await waitForTranslationsPopupEvent("popuphidden", () => {
+      click(
+        getByL10nId("translations-panel-translate-button"),
+        "Start translating by clicking the translate button."
+      );
+    });
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await resolveDownloads(1);
+
+    const { locale } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The icon presents the locale."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The pages H1 is translated.",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    info(
+      "Simulate clicking always-translate-language in the settings menu, " +
+        "adding the document language to the alwaysTranslateLanguages pref"
+    );
+    await openSettingsMenu();
+
+    await assertIsAlwaysTranslateLanguage("es", false);
+    await toggleAlwaysTranslateLanguage();
+    await assertIsAlwaysTranslateLanguage("es", true);
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The continues to present the locale without pending downloads."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The pages H1 is translated.",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    info(
+      "Simulate clicking always-translate-language in the settings menu " +
+        "removing the document language from the alwaysTranslateLanguages pref"
+    );
+    await assertIsAlwaysTranslateLanguage("es", true);
+    await toggleAlwaysTranslateLanguage();
+    await assertIsAlwaysTranslateLanguage("es", false);
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "Only the button appears"
+    );
+
+    info(
+      "The page should no longer automatically translated because the document language " +
+        "should be removed from the always-translate pref"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await cleanup();
+  }
+);
+
+/**
+ * Tests the effect of unchecking the always-translate language menuitem after the page has
+ * been manually restored to its original form.
+ * This should have no effect on the page, and further page loads should no longer auto-translate.
+ */
+add_task(
+  async function test_deactivate_always_translate_language_after_restore() {
+    const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+      page: SPANISH_PAGE_URL,
+      languagePairs: LANGUAGE_PAIRS,
+      prefs: [["browser.translations.alwaysTranslateLanguages", "pl,fr"]],
+    });
+
+    const { button } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The translations button is visible."
+    );
+
+    info(
+      'The document language "es" is not in the alwaysTranslateLanguages pref, ' +
+        "so the page should be untranslated, in its original form"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    info(
+      "Simulate clicking always-translate-language in the settings menu, " +
+        "adding the document language to the alwaysTranslateLanguages pref"
+    );
+    await openSettingsMenu();
+
+    await assertIsAlwaysTranslateLanguage("es", false);
+    await toggleAlwaysTranslateLanguage();
+    await assertIsAlwaysTranslateLanguage("es", true);
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await resolveDownloads(1);
+
+    const { locale } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The icon presents the locale."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    info(
+      "The page should now be automatically translated because the document language " +
+        "should be added to the always-translate pref"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is translated automatically",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    await navigate(
+      SPANISH_PAGE_URL_DOT_ORG,
+      "Navigate to a different Spanish page"
+    );
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await resolveDownloads(1);
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The icon presents the locale."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    info(
+      "The page should now be automatically translated because the document language " +
+        "should be added to the always-translate pref"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is translated automatically",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    await waitForTranslationsPopupEvent("popupshown", () => {
+      click(button, "Re-opening the popup");
+    });
+
+    await waitForTranslationsPopupEvent("popuphidden", () => {
+      click(
+        getByL10nId("translations-panel-restore-button"),
+        "Click the restore language button."
+      );
+    });
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The button is reverted to have an icon."
+    );
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is restored to Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    info(
+      "Simulate clicking always-translate-language in the settings menu, " +
+        "removing the document language to the alwaysTranslateLanguages pref"
+    );
+    await openSettingsMenu();
+
+    await assertIsAlwaysTranslateLanguage("es", true);
+    await toggleAlwaysTranslateLanguage();
+    await assertIsAlwaysTranslateLanguage("es", false);
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The button shows only the icon."
+    );
+
+    await navigate(SPANISH_PAGE_URL_DOT_ORG, "Reload the page");
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The button shows only the icon."
+    );
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is restored to Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await cleanup();
+  }
+);
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_basics.js b/browser/components/translations/tests/browser/browser_translations_panel_basics.js
new file mode 100644
index 0000000000..df2b0da4e5
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_basics.js
@@ -0,0 +1,94 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests a basic panel open, translation, and restoration to the original language.
+ */
+add_task(async function test_translations_panel_basics() {
+  const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  const { button } = await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: false, icon: true },
+    "The button is available."
+  );
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-translate-button"),
+      "Start translating by clicking the translate button."
+    );
+  });
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: true, locale: false, icon: true },
+    "The icon presents the loading indicator."
+  );
+
+  await resolveDownloads(1);
+
+  const { locale } = await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: true, icon: true },
+    "The icon presents the locale."
+  );
+
+  is(locale.innerText, "en", "The English language tag is shown.");
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The pages H1 is translated.",
+      getH1,
+      "DON QUIJOTE DE LA MANCHA [es to en, html]"
+    );
+  });
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Re-opening the popup");
+  });
+
+  ok(
+    getByL10nId("translations-panel-translate-button").disabled,
+    "The translate button is disabled when re-opening."
+  );
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-restore-button"),
+      "Click the restore language button."
+    );
+  });
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is restored to Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: false, icon: true },
+    "The button is reverted to have an icon."
+  );
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_beta_langs.js b/browser/components/translations/tests/browser/browser_translations_panel_beta_langs.js
new file mode 100644
index 0000000000..f44f2ad9e8
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_beta_langs.js
@@ -0,0 +1,66 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests that languages are displayed correctly as being in beta or not.
+ */
+add_task(async function test_translations_panel_display_beta_languages() {
+  const { cleanup } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  function assertBetaDisplay(selectElement) {
+    const betaL10nId = "translations-panel-displayname-beta";
+    const options = selectElement.querySelectorAll("menuitem");
+    if (options.length === 0) {
+      throw new Error("Could not find the menuitems.");
+    }
+
+    for (const option of options) {
+      for (const languagePair of LANGUAGE_PAIRS) {
+        if (
+          languagePair.fromLang === option.value ||
+          languagePair.toLang === option.value
+        ) {
+          if (option.getAttribute("data-l10n-id") === betaL10nId) {
+            is(
+              languagePair.isBeta,
+              true,
+              `Since data-l10n-id was ${betaL10nId} for ${option.value}, then it must be part of a beta language pair, but it was not.`
+            );
+          }
+          if (!languagePair.isBeta) {
+            is(
+              option.getAttribute("data-l10n-id") === betaL10nId,
+              false,
+              `Since the languagePair is non-beta, the language option ${option.value} should not have a data-l10-id of ${betaL10nId}, but it does.`
+            );
+          }
+        }
+      }
+    }
+  }
+
+  const { button } = await assertTranslationsButton(
+    { button: true },
+    "The button is available."
+  );
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  assertBetaDisplay(document.getElementById("translations-panel-to"));
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-translate-cancel"),
+      "Click the cancel button."
+    );
+  });
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_button.js b/browser/components/translations/tests/browser/browser_translations_panel_button.js
new file mode 100644
index 0000000000..57e09260fb
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_button.js
@@ -0,0 +1,80 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Test that the translations button is correctly visible when navigating between pages.
+ */
+add_task(async function test_button_visible_navigation() {
+  info("Start at a page in Spanish.");
+  const { cleanup } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  await assertTranslationsButton(
+    { button: true },
+    "The button should be visible since the page can be translated from Spanish."
+  );
+
+  navigate(ENGLISH_PAGE_URL, "Navigate to an English page.");
+
+  await assertTranslationsButton(
+    { button: false },
+    "The button should be invisible since the page is in English."
+  );
+
+  navigate(SPANISH_PAGE_URL, "Navigate back to a Spanish page.");
+
+  await assertTranslationsButton(
+    { button: true },
+    "The button should be visible again since the page is in Spanish."
+  );
+
+  await cleanup();
+});
+
+/**
+ * Test that the translations button is correctly visible when opening and switch tabs.
+ */
+add_task(async function test_button_visible() {
+  info("Start at a page in Spanish.");
+
+  const { cleanup, tab: spanishTab } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  await assertTranslationsButton(
+    { button: true },
+    "The button should be visible since the page can be translated from Spanish."
+  );
+
+  const { removeTab, tab: englishTab } = await addTab(
+    ENGLISH_PAGE_URL,
+    "Creating a new tab for a page in English."
+  );
+
+  await assertTranslationsButton(
+    { button: false },
+    "The button should be invisible since the tab is in English."
+  );
+
+  await switchTab(spanishTab);
+
+  await assertTranslationsButton(
+    { button: true },
+    "The button should be visible again since the page is in Spanish."
+  );
+
+  await switchTab(englishTab);
+
+  await assertTranslationsButton(
+    { button: false },
+    "Don't show for english pages"
+  );
+
+  await removeTab();
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_cancel.js b/browser/components/translations/tests/browser/browser_translations_panel_cancel.js
new file mode 100644
index 0000000000..b9bf532d96
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_cancel.js
@@ -0,0 +1,32 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests a panel open, and hitting the cancel button.
+ */
+add_task(async function test_translations_panel_cancel() {
+  const { cleanup } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  const { button } = await assertTranslationsButton(
+    { button: true },
+    "The button is available."
+  );
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-translate-cancel"),
+      "Click the cancel button."
+    );
+  });
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_gear.js b/browser/components/translations/tests/browser/browser_translations_panel_gear.js
new file mode 100644
index 0000000000..46838accb4
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_gear.js
@@ -0,0 +1,42 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Test managing the languages menu item.
+ */
+add_task(async function test_translations_panel_manage_languages() {
+  const { cleanup } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  const { button } = await assertTranslationsButton(
+    { button: true },
+    "The button is available."
+  );
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  const gearIcon = getByL10nId("translations-panel-settings-button");
+  click(gearIcon, "Open the preferences menu");
+
+  const manageLanguages = getByL10nId(
+    "translations-panel-settings-manage-languages"
+  );
+  info("Choose to manage the languages.");
+  manageLanguages.doCommand();
+
+  await TestUtils.waitForCondition(
+    () => gBrowser.currentURI.spec === "about:preferences#general",
+    "Waiting for about:preferences to be opened."
+  );
+
+  info("Remove the about:preferences tab");
+  gBrowser.removeCurrentTab();
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_never_translate_language.js b/browser/components/translations/tests/browser/browser_translations_panel_never_translate_language.js
new file mode 100644
index 0000000000..c85443f457
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_never_translate_language.js
@@ -0,0 +1,343 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests the effect of toggling the never-translate-language menuitem.
+ * Checking the box on an untranslated page should immediately hide the button.
+ * The button should not appear again for sites in the disabled language.
+ */
+add_task(async function test_toggle_never_translate_language_menuitem() {
+  const { cleanup, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+    prefs: [["browser.translations.neverTranslateLanguages", "pl,fr"]],
+  });
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: false, icon: true },
+    "The translations button is visible."
+  );
+
+  info(
+    'The document language "es" is not in the neverTranslateLanguages pref, ' +
+      "so the page should be untranslated, in its original form."
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  info(
+    "Simulate clicking never-translate-language in the settings menu, " +
+      "adding the document language from the neverTranslateLanguages pref"
+  );
+  await openSettingsMenu();
+
+  await assertIsNeverTranslateLanguage("es", false);
+  await toggleNeverTranslateLanguage();
+  await assertIsNeverTranslateLanguage("es", true);
+
+  await assertTranslationsButton(
+    { button: false },
+    "The translations button should be invisible"
+  );
+
+  info(
+    "The page should still be in its original, untranslated form because " +
+      "the document language is in the neverTranslateLanguages pref"
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await navigate(SPANISH_PAGE_URL, "Reload the page");
+
+  await assertTranslationsButton(
+    { button: false },
+    "The translations button should be invisible"
+  );
+
+  info(
+    "The page should still be in its original, untranslated form because " +
+      "the document language is in the neverTranslateLanguages pref"
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await navigate(
+    SPANISH_PAGE_URL_DOT_ORG,
+    "Navigate to a different Spanish page"
+  );
+
+  await assertTranslationsButton(
+    { button: false },
+    "The translations button should be invisible"
+  );
+
+  info(
+    "The page should still be in its original, untranslated form because " +
+      "the document language is in the neverTranslateLanguages pref"
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await cleanup();
+});
+
+/**
+ * Tests the effect of toggling the never-translate-language menuitem on a page where
+ * where translation is already active.
+ * Checking the box on a translated page should restore the page and hide the button.
+ * The button should not appear again for sites in the disabled language.
+ */
+add_task(
+  async function test_toggle_never_translate_language_menuitem_with_active_translations() {
+    const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+      page: SPANISH_PAGE_URL,
+      languagePairs: LANGUAGE_PAIRS,
+      prefs: [["browser.translations.neverTranslateLanguages", "pl,fr"]],
+    });
+
+    const { button } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The button is available."
+    );
+
+    info(
+      'The document language "es" is not in the alwaysTranslateLanguages pref, ' +
+        "so the page should be untranslated, in its original form"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await waitForTranslationsPopupEvent("popupshown", () => {
+      click(button, "Opening the popup");
+    });
+
+    await waitForTranslationsPopupEvent("popuphidden", () => {
+      click(
+        getByL10nId("translations-panel-translate-button"),
+        "Start translating by clicking the translate button."
+      );
+    });
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await resolveDownloads(1);
+
+    const { locale } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The icon presents the locale."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The pages H1 is translated.",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    info(
+      "Simulate clicking never-translate-language in the settings menu, " +
+        "adding the document language from the neverTranslateLanguages pref"
+    );
+    await openSettingsMenu();
+
+    await assertIsNeverTranslateLanguage("es", false);
+    await toggleNeverTranslateLanguage();
+    await assertIsNeverTranslateLanguage("es", true);
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible"
+    );
+
+    info(
+      "The page should still be in its original, untranslated form because " +
+        "the document language is in the neverTranslateLanguages pref"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await navigate(SPANISH_PAGE_URL, "Reload the page");
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible"
+    );
+
+    info(
+      "The page should still be in its original, untranslated form because " +
+        "the document language is in the neverTranslateLanguages pref"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await cleanup();
+  }
+);
+
+/**
+ * Tests the effect of toggling the never-translate-language menuitem on a page where
+ * where translation is already active via always-translate.
+ * Checking the box on a translated page should restore the page and hide the button.
+ * The language should be moved from always-translate to never-translate.
+ * The button should not appear again for sites in the disabled language.
+ */
+add_task(
+  async function test_toggle_never_translate_language_menuitem_with_always_translate_active() {
+    const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+      page: SPANISH_PAGE_URL,
+      languagePairs: LANGUAGE_PAIRS,
+      prefs: [
+        ["browser.translations.alwaysTranslateLanguages", "uk,it"],
+        ["browser.translations.neverTranslateLanguages", "pl,fr"],
+      ],
+    });
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The button is available."
+    );
+
+    info(
+      "Simulate clicking always-translate-language in the settings menu, " +
+        "adding the document language to the alwaysTranslateLanguages pref"
+    );
+    await openSettingsMenu();
+
+    await assertIsAlwaysTranslateLanguage("es", false);
+    await assertIsNeverTranslateLanguage("es", false);
+
+    await toggleAlwaysTranslateLanguage();
+
+    await assertIsAlwaysTranslateLanguage("es", true);
+    await assertIsNeverTranslateLanguage("es", false);
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await resolveDownloads(1);
+
+    const { locale } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The icon presents the locale."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The pages H1 is translated.",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    info(
+      "Simulate clicking never-translate-language in the settings menu, " +
+        "adding the document language from the neverTranslateLanguages pref " +
+        "and removing it from the alwaysTranslateLanguages pref"
+    );
+    await openSettingsMenu();
+
+    await assertIsAlwaysTranslateLanguage("es", true);
+    await assertIsNeverTranslateLanguage("es", false);
+
+    await toggleNeverTranslateLanguage();
+
+    await assertIsAlwaysTranslateLanguage("es", false);
+    await assertIsNeverTranslateLanguage("es", true);
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible"
+    );
+
+    info(
+      "The page should still be in its original, untranslated form because " +
+        "the document language is in the neverTranslateLanguages pref"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await navigate(SPANISH_PAGE_URL, "Reload the page");
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible"
+    );
+
+    info(
+      "The page should still be in its original, untranslated form because " +
+        "the document language is in the neverTranslateLanguages pref"
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await cleanup();
+  }
+);
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_never_translate_site.js b/browser/components/translations/tests/browser/browser_translations_panel_never_translate_site.js
new file mode 100644
index 0000000000..b54b5a4a2c
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_never_translate_site.js
@@ -0,0 +1,432 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests the effect of toggling the never-translate-site menuitem.
+ * Checking the box on an untranslated page should immediately hide the button.
+ * The button should not appear again for sites that share the same content principal
+ * of the disabled site.
+ */
+add_task(async function test_toggle_never_translate_site_menuitem() {
+  const { cleanup, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+    permissionsUrls: [SPANISH_PAGE_URL],
+  });
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: false, icon: true },
+    "The translations button is visible."
+  );
+
+  info(
+    "Translations permissions are currently allowed for this test page " +
+      "and the page should be untranslated, in its original form."
+  );
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  info(
+    "Simulate clicking never-translate-site in the settings menu, " +
+      "denying translations permissions for this content window principal"
+  );
+  await openSettingsMenu();
+
+  await assertIsNeverTranslateSite(SPANISH_PAGE_URL, false);
+  await toggleNeverTranslateSite();
+  await assertIsNeverTranslateSite(SPANISH_PAGE_URL, true);
+
+  await assertTranslationsButton(
+    { button: false },
+    "The translations button should be invisible"
+  );
+
+  info("The page should still be in its original, untranslated form");
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await navigate(SPANISH_PAGE_URL, "Reload the page");
+
+  await assertTranslationsButton(
+    { button: false },
+    "The translations button should be invisible"
+  );
+
+  info("The page should still be in its original, untranslated form");
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await navigate(
+    SPANISH_PAGE_URL_2,
+    "Navigate to a Spanish page with the same content principal"
+  );
+
+  await assertTranslationsButton(
+    { button: false },
+    "The translations button should be invisible, because this content principal is denied"
+  );
+
+  info("The page should still be in its original, untranslated form");
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await navigate(
+    SPANISH_PAGE_URL_DOT_ORG,
+    "Navigate to a Spanish page with a different content principal"
+  );
+
+  await assertTranslationsButton(
+    { button: false },
+    "The translations button should be visible, because this content principal " +
+      "has not been denied translations permissions"
+  );
+
+  info("The page should still be in its original, untranslated form");
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await cleanup();
+});
+
+/**
+ * Tests the effect of toggling the never-translate-site menuitem on a page where
+ * where translation is already active.
+ * Checking the box on a translated page should restore the page and hide the button.
+ * The button should not appear again for sites that share the same content principal
+ * of the disabled site.
+ */
+add_task(
+  async function test_toggle_never_translate_site_menuitem_with_active_translations() {
+    const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+      page: SPANISH_PAGE_URL,
+      languagePairs: LANGUAGE_PAIRS,
+      permissionsUrls: [SPANISH_PAGE_URL],
+    });
+
+    const { button } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The translations button is visible."
+    );
+
+    info(
+      "Translations permissions are currently allowed for this test page " +
+        "and the page should be untranslated, in its original form."
+    );
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await waitForTranslationsPopupEvent("popupshown", () => {
+      click(button, "Opening the popup");
+    });
+
+    await waitForTranslationsPopupEvent("popuphidden", () => {
+      click(
+        getByL10nId("translations-panel-translate-button"),
+        "Start translating by clicking the translate button."
+      );
+    });
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await resolveDownloads(1);
+
+    const { locale } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The icon presents the locale."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The pages H1 is translated.",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    info(
+      "Simulate clicking never-translate-site in the settings menu, " +
+        "denying translations permissions for this content window principal"
+    );
+    await openSettingsMenu();
+
+    await assertIsNeverTranslateSite(SPANISH_PAGE_URL, false);
+    await toggleNeverTranslateSite();
+    await assertIsNeverTranslateSite(SPANISH_PAGE_URL, true);
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible"
+    );
+
+    info("The page should still be in its original, untranslated form");
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await navigate(SPANISH_PAGE_URL, "Reload the page");
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible"
+    );
+
+    info("The page should still be in its original, untranslated form");
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await navigate(
+      SPANISH_PAGE_URL_2,
+      "Navigate to a Spanish page with the same content principal"
+    );
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible, because this content principal is denied"
+    );
+
+    info("The page should still be in its original, untranslated form");
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await navigate(
+      SPANISH_PAGE_URL_DOT_ORG,
+      "Navigate to a Spanish page with a different content principal"
+    );
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be visible, because this content principal " +
+        "has not been denied translations permissions"
+    );
+
+    info("The page should still be in its original, untranslated form");
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await cleanup();
+  }
+);
+
+/**
+ * Tests the effect of toggling the never-translate-site menuitem on a page where
+ * where translation is already active via always-translate.
+ * Checking the box on a translated page should restore the page and hide the button.
+ * The button should not appear again for sites that share the same content principal
+ * of the disabled site, and no auto-translation should occur.
+ * Other sites should still auto-translate for this language.
+ */
+add_task(
+  async function test_toggle_never_translate_site_menuitem_with_always_translate_active() {
+    const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+      page: SPANISH_PAGE_URL,
+      languagePairs: LANGUAGE_PAIRS,
+      prefs: [["browser.translations.alwaysTranslateLanguages", "uk,it"]],
+      permissionsUrls: [SPANISH_PAGE_URL],
+    });
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The button is available."
+    );
+
+    info(
+      "Simulate clicking always-translate-language in the settings menu, " +
+        "adding the document language to the alwaysTranslateLanguages pref"
+    );
+    await openSettingsMenu();
+
+    await assertIsAlwaysTranslateLanguage("es", false);
+    await assertIsNeverTranslateSite(SPANISH_PAGE_URL, false);
+
+    await toggleAlwaysTranslateLanguage();
+
+    await assertIsAlwaysTranslateLanguage("es", true);
+    await assertIsNeverTranslateSite(SPANISH_PAGE_URL, false);
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await resolveDownloads(1);
+
+    const { locale } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The icon presents the locale."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The pages H1 is translated.",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    info(
+      "Simulate clicking never-translate-site in the settings menu, " +
+        "denying translations permissions for this content window principal"
+    );
+    await openSettingsMenu();
+
+    await assertIsAlwaysTranslateLanguage("es", true);
+    await assertIsNeverTranslateSite(SPANISH_PAGE_URL, false);
+
+    await toggleNeverTranslateSite();
+
+    await assertIsAlwaysTranslateLanguage("es", true);
+    await assertIsNeverTranslateSite(SPANISH_PAGE_URL, true);
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible"
+    );
+
+    info("The page should still be in its original, untranslated form");
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await navigate(SPANISH_PAGE_URL, "Reload the page");
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible"
+    );
+
+    info("The page should still be in its original, untranslated form");
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await navigate(
+      SPANISH_PAGE_URL_2,
+      "Navigate to a Spanish page with the same content principal"
+    );
+
+    await assertTranslationsButton(
+      { button: false },
+      "The translations button should be invisible, because this content principal is denied"
+    );
+
+    info("The page should still be in its original, untranslated form");
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await navigate(
+      SPANISH_PAGE_URL_DOT_ORG,
+      "Navigate to a Spanish page with a different content principal"
+    );
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await resolveDownloads(1);
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: true, icon: true },
+      "The icon presents the locale."
+    );
+
+    is(locale.innerText, "en", "The English language tag is shown.");
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The pages H1 is translated.",
+        getH1,
+        "DON QUIJOTE DE LA MANCHA [es to en, html]"
+      );
+    });
+
+    await cleanup();
+  }
+);
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_retry.js b/browser/components/translations/tests/browser/browser_translations_panel_retry.js
new file mode 100644
index 0000000000..e9b3f93257
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_retry.js
@@ -0,0 +1,80 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests translating, and then immediately translating to a new language.
+ */
+add_task(async function test_translations_panel_retry() {
+  const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  const { button } = await assertTranslationsButton(
+    { button: true },
+    "The button is available."
+  );
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-translate-button"),
+      "Start translating by clicking the translate button."
+    );
+  });
+
+  await resolveDownloads(1);
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The pages H1 is translated.",
+      getH1,
+      "DON QUIJOTE DE LA MANCHA [es to en, html]"
+    );
+  });
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Re-opening the popup");
+  });
+
+  info('Switch to language to "fr"');
+  const toSelect = getById("translations-panel-to");
+  toSelect.value = "fr";
+  toSelect.dispatchEvent(new Event("command"));
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-translate-button"),
+      "Re-translate the page by clicking the translate button."
+    );
+  });
+
+  // This is a pivot language which requires 2 models.
+  await resolveDownloads(2);
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The pages H1 is translated using the changed languages.",
+      getH1,
+      "DON QUIJOTE DE LA MANCHA [es to fr, html]"
+    );
+  });
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_panel_switch_languages.js b/browser/components/translations/tests/browser/browser_translations_panel_switch_languages.js
new file mode 100644
index 0000000000..58bcb212d7
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_panel_switch_languages.js
@@ -0,0 +1,97 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests switching the language.
+ */
+add_task(async function test_translations_panel_switch_language() {
+  const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  const { button } = await assertTranslationsButton(
+    { button: true },
+    "The button is available."
+  );
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  const translateButton = getByL10nId("translations-panel-translate-button");
+  const fromSelect = getById("translations-panel-from");
+  const toSelect = getById("translations-panel-to");
+
+  ok(!translateButton.disabled, "The translate button starts as enabled");
+  is(fromSelect.value, "es", "The from select starts as Spanish");
+  is(toSelect.value, "en", "The to select starts as English");
+
+  info('Switch from language to "es"');
+  fromSelect.value = "en";
+  fromSelect.dispatchEvent(new Event("command"));
+
+  ok(
+    translateButton.disabled,
+    "The translate button is disabled when the languages are the same"
+  );
+
+  info('Switch from language back to "es"');
+  fromSelect.value = "es";
+  fromSelect.dispatchEvent(new Event("command"));
+
+  ok(
+    !translateButton.disabled,
+    "When the languages are different it can be translated"
+  );
+
+  info("Switch to language to nothing");
+  fromSelect.value = "";
+  fromSelect.dispatchEvent(new Event("command"));
+
+  ok(
+    translateButton.disabled,
+    "The translate button is disabled nothing is selected."
+  );
+
+  info('Switch from language to "en"');
+  fromSelect.value = "en";
+  fromSelect.dispatchEvent(new Event("command"));
+
+  info('Switch to language to "fr"');
+  toSelect.value = "fr";
+  toSelect.dispatchEvent(new Event("command"));
+
+  ok(!translateButton.disabled, "The translate button can now be used");
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      translateButton,
+      "Start translating by clicking the translate button."
+    );
+  });
+
+  await resolveDownloads(1);
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The pages H1 is translated using the changed languages.",
+      getH1,
+      "DON QUIJOTE DE LA MANCHA [en to fr, html]"
+    );
+  });
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_telemetry_open_panel.js b/browser/components/translations/tests/browser/browser_translations_telemetry_open_panel.js
new file mode 100644
index 0000000000..41aa730863
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_telemetry_open_panel.js
@@ -0,0 +1,73 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests the telemetry event for opening the translations panel.
+ */
+add_task(async function test_translations_telemetry_open_panel() {
+  const { cleanup } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  await TestTranslationsTelemetry.assertEvent(
+    "OpenPanel",
+    Glean.translationsPanel.open,
+    {
+      expectedLength: 0,
+    }
+  );
+
+  const { button } = await assertTranslationsButton(
+    { button: true },
+    "The button is available."
+  );
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-translate-cancel"),
+      "Click the cancel button."
+    );
+  });
+
+  await TestTranslationsTelemetry.assertEvent(
+    "OpenPanel",
+    Glean.translationsPanel.open,
+    {
+      expectedLength: 1,
+      finalValuePredicates: [
+        value => value.extra.opened_from === "translationsButton",
+      ],
+    }
+  );
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-translate-cancel"),
+      "Click the cancel button."
+    );
+  });
+
+  await TestTranslationsTelemetry.assertEvent(
+    "OpenPanel",
+    Glean.translationsPanel.open,
+    {
+      expectedLength: 2,
+      allValuePredicates: [
+        value => value.extra.opened_from === "translationsButton",
+      ],
+    }
+  );
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_telemetry_translation_failure.js b/browser/components/translations/tests/browser/browser_translations_telemetry_translation_failure.js
new file mode 100644
index 0000000000..1268e6452b
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_telemetry_translation_failure.js
@@ -0,0 +1,195 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+const { PromiseTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/PromiseTestUtils.sys.mjs"
+);
+
+/**
+ * Tests the telemetry event for a manual translation request failure.
+ */
+add_task(
+  async function test_translations_telemetry_manual_translation_failure() {
+    PromiseTestUtils.expectUncaughtRejection(
+      /Intentionally rejecting downloads./
+    );
+
+    const { cleanup, rejectDownloads, runInPage } = await loadTestPage({
+      page: SPANISH_PAGE_URL,
+      languagePairs: LANGUAGE_PAIRS,
+    });
+
+    const { button } = await assertTranslationsButton(
+      { button: true, circleArrows: false, locale: false, icon: true },
+      "The button is available."
+    );
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await TestTranslationsTelemetry.assertCounter(
+      "RequestCount",
+      Glean.translations.requestsCount,
+      0
+    );
+    await TestTranslationsTelemetry.assertRate(
+      "ErrorRate",
+      Glean.translations.errorRate,
+      {
+        expectedNumerator: 0,
+        expectedDenominator: 0,
+      }
+    );
+    await TestTranslationsTelemetry.assertEvent(
+      "TranslationRequest",
+      Glean.translations.translationRequest,
+      {
+        expectedLength: 0,
+      }
+    );
+
+    await waitForTranslationsPopupEvent("popupshown", () => {
+      click(button, "Opening the popup");
+    });
+
+    await waitForTranslationsPopupEvent("popuphidden", () => {
+      click(
+        getByL10nId("translations-panel-translate-button"),
+        "Start translating by clicking the translate button."
+      );
+    });
+
+    await assertTranslationsButton(
+      { button: true, circleArrows: true, locale: false, icon: true },
+      "The icon presents the loading indicator."
+    );
+
+    await rejectDownloads(1);
+
+    await runInPage(async TranslationsTest => {
+      const { getH1 } = TranslationsTest.getSelectors();
+      await TranslationsTest.assertTranslationResult(
+        "The page's H1 is in Spanish.",
+        getH1,
+        "Don Quijote de La Mancha"
+      );
+    });
+
+    await TestTranslationsTelemetry.assertCounter(
+      "RequestCount",
+      Glean.translations.requestsCount,
+      1
+    );
+    await TestTranslationsTelemetry.assertRate(
+      "ErrorRate",
+      Glean.translations.errorRate,
+      {
+        expectedNumerator: 1,
+        expectedDenominator: 1,
+      }
+    );
+    await TestTranslationsTelemetry.assertEvent(
+      "Error",
+      Glean.translations.error,
+      {
+        expectedLength: 1,
+        finalValuePredicates: [
+          value =>
+            value.extra.reason === "Error: Intentionally rejecting downloads.",
+        ],
+      }
+    );
+    await TestTranslationsTelemetry.assertEvent(
+      "TranslationRequest",
+      Glean.translations.translationRequest,
+      {
+        expectedLength: 1,
+        finalValuePredicates: [
+          value => value.extra.from_language === "es",
+          value => value.extra.to_language === "en",
+          value => value.extra.auto_translate === "false",
+        ],
+      }
+    );
+
+    await cleanup();
+  }
+);
+
+/**
+ * Tests the telemetry event for an automatic translation request failure.
+ */
+add_task(async function test_translations_telemetry_auto_translation_failure() {
+  PromiseTestUtils.expectUncaughtRejection(
+    /Intentionally rejecting downloads./
+  );
+
+  const { cleanup, rejectDownloads, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+    prefs: [["browser.translations.alwaysTranslateLanguages", "es"]],
+  });
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: true, locale: false, icon: true },
+    "The icon presents the loading indicator."
+  );
+
+  await rejectDownloads(1);
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await TestTranslationsTelemetry.assertCounter(
+    "RequestCount",
+    Glean.translations.requestsCount,
+    1
+  );
+  await TestTranslationsTelemetry.assertRate(
+    "ErrorRate",
+    Glean.translations.errorRate,
+    {
+      expectedNumerator: 1,
+      expectedDenominator: 1,
+    }
+  );
+  await TestTranslationsTelemetry.assertEvent(
+    "Error",
+    Glean.translations.error,
+    {
+      expectedLength: 1,
+      finalValuePredicates: [
+        value =>
+          value.extra.reason === "Error: Intentionally rejecting downloads.",
+      ],
+    }
+  );
+  await TestTranslationsTelemetry.assertEvent(
+    "TranslationRequest",
+    Glean.translations.translationRequest,
+    {
+      expectedLength: 1,
+      finalValuePredicates: [
+        value => value.extra.from_language === "es",
+        value => value.extra.to_language === "en",
+        value => value.extra.auto_translate === "true",
+      ],
+    }
+  );
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/browser_translations_telemetry_translation_request.js b/browser/components/translations/tests/browser/browser_translations_telemetry_translation_request.js
new file mode 100644
index 0000000000..ce22615630
--- /dev/null
+++ b/browser/components/translations/tests/browser/browser_translations_telemetry_translation_request.js
@@ -0,0 +1,173 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * Tests the telemetry event for a manual translation request.
+ */
+add_task(async function test_translations_telemetry_manual_translation() {
+  const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+  });
+
+  const { button } = await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: false, icon: true },
+    "The button is available."
+  );
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The page's H1 is in Spanish.",
+      getH1,
+      "Don Quijote de La Mancha"
+    );
+  });
+
+  await TestTranslationsTelemetry.assertCounter(
+    "RequestCount",
+    Glean.translations.requestsCount,
+    0
+  );
+  await TestTranslationsTelemetry.assertRate(
+    "ErrorRate",
+    Glean.translations.errorRate,
+    {
+      expectedNumerator: 0,
+      expectedDenominator: 0,
+    }
+  );
+  await TestTranslationsTelemetry.assertEvent(
+    "TranslationRequest",
+    Glean.translations.translationRequest,
+    {
+      expectedLength: 0,
+    }
+  );
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  await waitForTranslationsPopupEvent("popuphidden", () => {
+    click(
+      getByL10nId("translations-panel-translate-button"),
+      "Start translating by clicking the translate button."
+    );
+  });
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: true, locale: false, icon: true },
+    "The icon presents the loading indicator."
+  );
+
+  await resolveDownloads(1);
+
+  const { locale } = await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: true, icon: true },
+    "The icon presents the locale."
+  );
+
+  is(locale.innerText, "en", "The English language tag is shown.");
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The pages H1 is translated.",
+      getH1,
+      "DON QUIJOTE DE LA MANCHA [es to en, html]"
+    );
+  });
+
+  await TestTranslationsTelemetry.assertCounter(
+    "RequestCount",
+    Glean.translations.requestsCount,
+    1
+  );
+  await TestTranslationsTelemetry.assertRate(
+    "ErrorRate",
+    Glean.translations.errorRate,
+    {
+      expectedNumerator: 0,
+      expectedDenominator: 1,
+    }
+  );
+  await TestTranslationsTelemetry.assertEvent(
+    "TranslationRequest",
+    Glean.translations.translationRequest,
+    {
+      expectedLength: 1,
+      finalValuePredicates: [
+        value => value.extra.from_language === "es",
+        value => value.extra.to_language === "en",
+        value => value.extra.auto_translate === "false",
+      ],
+    }
+  );
+
+  await cleanup();
+});
+
+/**
+ * Tests the telemetry event for an automatic translation request.
+ */
+add_task(async function test_translations_telemetry_auto_translation() {
+  const { cleanup, resolveDownloads, runInPage } = await loadTestPage({
+    page: SPANISH_PAGE_URL,
+    languagePairs: LANGUAGE_PAIRS,
+    prefs: [["browser.translations.alwaysTranslateLanguages", "es"]],
+  });
+
+  await assertTranslationsButton(
+    { button: true, circleArrows: true, locale: false, icon: true },
+    "The icon presents the loading indicator."
+  );
+
+  await resolveDownloads(1);
+
+  const { locale } = await assertTranslationsButton(
+    { button: true, circleArrows: false, locale: true, icon: true },
+    "The icon presents the locale."
+  );
+
+  is(locale.innerText, "en", "The English language tag is shown.");
+
+  await runInPage(async TranslationsTest => {
+    const { getH1 } = TranslationsTest.getSelectors();
+    await TranslationsTest.assertTranslationResult(
+      "The pages H1 is translated.",
+      getH1,
+      "DON QUIJOTE DE LA MANCHA [es to en, html]"
+    );
+  });
+
+  await TestTranslationsTelemetry.assertCounter(
+    "RequestCount",
+    Glean.translations.requestsCount,
+    1
+  );
+  await TestTranslationsTelemetry.assertRate(
+    "ErrorRate",
+    Glean.translations.errorRate,
+    {
+      expectedNumerator: 0,
+      expectedDenominator: 1,
+    }
+  );
+  await TestTranslationsTelemetry.assertEvent(
+    "TranslationRequest",
+    Glean.translations.translationRequest,
+    {
+      expectedLength: 1,
+      finalValuePredicates: [
+        value => value.extra.from_language === "es",
+        value => value.extra.to_language === "en",
+        value => value.extra.auto_translate === "true",
+      ],
+    }
+  );
+
+  await cleanup();
+});
diff --git a/browser/components/translations/tests/browser/head.js b/browser/components/translations/tests/browser/head.js
new file mode 100644
index 0000000000..56839971b7
--- /dev/null
+++ b/browser/components/translations/tests/browser/head.js
@@ -0,0 +1,348 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+Services.scriptloader.loadSubScript(
+  "chrome://mochitests/content/browser/toolkit/components/translations/tests/browser/shared-head.js",
+  this
+);
+
+/**
+ * Assert some property about the translations button.
+ *
+ * @param {Record<string, boolean>} visibleAssertions
+ * @param {string} message The message for the assertion.
+ * @returns {HTMLElement}
+ */
+async function assertTranslationsButton(visibleAssertions, message) {
+  const elements = {
+    button: document.getElementById("translations-button"),
+    icon: document.getElementById("translations-button-icon"),
+    circleArrows: document.getElementById("translations-button-circle-arrows"),
+    locale: document.getElementById("translations-button-locale"),
+  };
+
+  for (const [name, element] of Object.entries(elements)) {
+    if (!element) {
+      throw new Error("Could not find the " + name);
+    }
+  }
+
+  try {
+    // Test that the visibilities match.
+    await TestUtils.waitForCondition(() => {
+      for (const [name, visible] of Object.entries(visibleAssertions)) {
+        if (elements[name].hidden === visible) {
+          return false;
+        }
+      }
+      return true;
+    }, message);
+  } catch (error) {
+    // On a mismatch, report it.
+    for (const [name, expected] of Object.entries(visibleAssertions)) {
+      is(!elements[name].hidden, expected, `Visibility for "${name}"`);
+    }
+  }
+
+  ok(true, message);
+
+  return elements;
+}
+
+/**
+ * A convenience function to open the settings menu of the
+ * translations panel. Fails the test if the menu cannot be opened.
+ */
+async function openSettingsMenu() {
+  const { button } = await assertTranslationsButton(
+    { button: true },
+    "The button is available."
+  );
+
+  await waitForTranslationsPopupEvent("popupshown", () => {
+    click(button, "Opening the popup");
+  });
+
+  const gearIcon = getByL10nId("translations-panel-settings-button");
+  click(gearIcon, "Open the settings menu");
+}
+
+/**
+ * Simulates the effect of clicking the always-translate-language menuitem.
+ * Requires that the settings menu of the translations panel is open,
+ * otherwise the test will fail.
+ */
+async function toggleAlwaysTranslateLanguage() {
+  const alwaysTranslateLanguage = getByL10nId(
+    "translations-panel-settings-always-translate-language"
+  );
+  info("Toggle the always-translate-language menuitem");
+  await alwaysTranslateLanguage.doCommand();
+}
+
+/**
+ * Simulates the effect of clicking the never-translate-language menuitem.
+ * Requires that the settings menu of the translations panel is open,
+ * otherwise the test will fail.
+ */
+async function toggleNeverTranslateLanguage() {
+  const neverTranslateLanguage = getByL10nId(
+    "translations-panel-settings-never-translate-language"
+  );
+  info("Toggle the never-translate-language menuitem");
+  await neverTranslateLanguage.doCommand();
+}
+
+/**
+ * Simulates the effect of clicking the never-translate-site menuitem.
+ * Requires that the settings menu of the translations panel is open,
+ * otherwise the test will fail.
+ */
+async function toggleNeverTranslateSite() {
+  const neverTranslateSite = getByL10nId(
+    "translations-panel-settings-never-translate-site"
+  );
+  info("Toggle the never-translate-site menuitem");
+  await neverTranslateSite.doCommand();
+}
+
+/**
+ * Asserts that the always-translate-language checkbox matches the expected checked state.
+ *
+ * @param {string} langTag - A BCP-47 language tag
+ * @param {boolean} expectChecked - Whether the checkbox should be checked
+ */
+async function assertIsAlwaysTranslateLanguage(langTag, expectChecked) {
+  await assertCheckboxState(
+    "translations-panel-settings-always-translate-language",
+    expectChecked
+  );
+}
+
+/**
+ * Asserts that the never-translate-language checkbox matches the expected checked state.
+ *
+ * @param {string} langTag - A BCP-47 language tag
+ * @param {boolean} expectChecked - Whether the checkbox should be checked
+ */
+async function assertIsNeverTranslateLanguage(langTag, expectChecked) {
+  await assertCheckboxState(
+    "translations-panel-settings-never-translate-language",
+    expectChecked
+  );
+}
+
+/**
+ * Asserts that the never-translate-site checkbox matches the expected checked state.
+ *
+ * @param {string} url - The url of a website
+ * @param {boolean} expectChecked - Whether the checkbox should be checked
+ */
+async function assertIsNeverTranslateSite(url, expectChecked) {
+  await assertCheckboxState(
+    "translations-panel-settings-never-translate-site",
+    expectChecked
+  );
+}
+
+/**
+ * Asserts that the state of a checkbox with a given dataL10nId is
+ * checked or not, based on the value of expected being true or false.
+ *
+ * @param {string} dataL10nId - The data-l10n-id of the checkbox.
+ * @param {boolean} expectChecked - Whether the checkbox should be checked.
+ */
+async function assertCheckboxState(dataL10nId, expectChecked) {
+  const menuItems = getAllByL10nId(dataL10nId);
+  for (const menuItem of menuItems) {
+    await TestUtils.waitForCondition(
+      () =>
+        menuItem.getAttribute("checked") === (expectChecked ? "true" : "false"),
+      "Waiting for checkbox state"
+    );
+    is(
+      menuItem.getAttribute("checked"),
+      expectChecked ? "true" : "false",
+      `Should match expected checkbox state for ${dataL10nId}`
+    );
+  }
+}
+
+/**
+ * Navigate to a URL and indicate a message as to why.
+ */
+async function navigate(url, message) {
+  info(message);
+
+  // Load a blank page first to ensure that tests don't hang.
+  // I don't know why this is needed, but it appears to be necessary.
+  BrowserTestUtils.loadURIString(gBrowser.selectedBrowser, BLANK_PAGE);
+  await BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser);
+
+  BrowserTestUtils.loadURIString(gBrowser.selectedBrowser, url);
+  await BrowserTestUtils.browserLoaded(gBrowser.selectedBrowser);
+}
+
+/**
+ * Add a tab to the page
+ *
+ * @param {string} url
+ */
+async function addTab(url) {
+  info(`Adding tab for ` + url);
+  const tab = await BrowserTestUtils.openNewForegroundTab(
+    gBrowser,
+    url,
+    true // Wait for laod
+  );
+  return {
+    tab,
+    removeTab() {
+      BrowserTestUtils.removeTab(tab);
+    },
+  };
+}
+
+async function switchTab(tab) {
+  info("Switching tabs");
+  await BrowserTestUtils.switchTab(gBrowser, tab);
+}
+
+function click(button, message) {
+  info(message);
+  EventUtils.synthesizeMouseAtCenter(button, {});
+}
+
+/**
+ * @param {Element} element
+ * @returns {boolean}
+ */
+function isVisible(element) {
+  const win = element.ownerDocument.ownerGlobal;
+  const { visibility, display } = win.getComputedStyle(element);
+  return visibility === "visible" && display !== "none";
+}
+
+/**
+ * Get an element by its l10n id, as this is a user-visible way to find an element.
+ * The `l10nId` represents the text that a user would actually see.
+ *
+ * @param {string} l10nId
+ * @param {Document} doc
+ * @returns {Element}
+ */
+function getByL10nId(l10nId, doc = document) {
+  const elements = doc.querySelectorAll(`[data-l10n-id="${l10nId}"]`);
+  if (elements.length === 0) {
+    throw new Error("Could not find the element by l10n id: " + l10nId);
+  }
+  for (const element of elements) {
+    if (isVisible(element)) {
+      return element;
+    }
+  }
+  throw new Error("The element is not visible in the DOM: " + l10nId);
+}
+
+/**
+ * Get all elements that match the l10n id.
+ *
+ * @param {string} l10nId
+ * @param {Document} doc
+ * @returns {Element}
+ */
+function getAllByL10nId(l10nId, doc = document) {
+  const elements = doc.querySelectorAll(`[data-l10n-id="${l10nId}"]`);
+  if (elements.length === 0) {
+    throw new Error("Could not find the element by l10n id: " + l10nId);
+  }
+  return elements;
+}
+
+/**
+ * @param {string} id
+ * @param {Document} [doc]
+ * @returns {Element}
+ */
+function getById(id, doc = document) {
+  const element = doc.getElementById(id);
+  if (!element) {
+    throw new Error("Could not find the element by id: #" + id);
+  }
+  if (isVisible(element)) {
+    return element;
+  }
+  throw new Error("The element is not visible in the DOM: #" + id);
+}
+
+/**
+ * A non-throwing version of `getByL10nId`.
+ *
+ * @param {string} l10nId
+ * @returns {Element | null}
+ */
+function maybeGetByL10nId(l10nId, doc = document) {
+  const selector = `[data-l10n-id="${l10nId}"]`;
+  const elements = doc.querySelectorAll(selector);
+  for (const element of elements) {
+    if (isVisible(element)) {
+      return element;
+    }
+  }
+  return null;
+}
+
+/**
+ * XUL popups will fire the popupshown and popuphidden events. These will fire for
+ * any type of popup in the browser. This function waits for one of those events, and
+ * checks that the viewId of the popup is PanelUI-profiler
+ *
+ * @param {"popupshown" | "popuphidden"} eventName
+ * @param {Function} callback
+ * @returns {Promise<void>}
+ */
+async function waitForTranslationsPopupEvent(eventName, callback) {
+  const panel = document.getElementById("translations-panel");
+  if (!panel) {
+    throw new Error("Unable to find the translations panel element.");
+  }
+  const promise = BrowserTestUtils.waitForEvent(panel, eventName);
+  callback();
+  info("Waiting for the translations panel popup to be shown");
+  await promise;
+  // Wait a single tick on the event loop.
+  await new Promise(resolve => setTimeout(resolve, 0));
+}
+
+/**
+ * When switching between between views in the popup panel, wait for the view to
+ * be fully shown.
+ *
+ * @param {Function} callback
+ */
+async function waitForViewShown(callback) {
+  const panel = document.getElementById("translations-panel");
+  if (!panel) {
+    throw new Error("Unable to find the translations panel element.");
+  }
+  const promise = BrowserTestUtils.waitForEvent(panel, "ViewShown");
+  callback();
+  info("Waiting for the translations panel view to be shown");
+  await promise;
+  await new Promise(resolve => setTimeout(resolve, 0));
+}
+
+const ENGLISH_PAGE_URL = TRANSLATIONS_TESTER_EN;
+const SPANISH_PAGE_URL = TRANSLATIONS_TESTER_ES;
+const SPANISH_PAGE_URL_2 = TRANSLATIONS_TESTER_ES_2;
+const SPANISH_PAGE_URL_DOT_ORG = TRANSLATIONS_TESTER_ES_DOT_ORG;
+const LANGUAGE_PAIRS = [
+  { fromLang: "es", toLang: "en", isBeta: false },
+  { fromLang: "en", toLang: "es", isBeta: false },
+  { fromLang: "fr", toLang: "en", isBeta: false },
+  { fromLang: "en", toLang: "fr", isBeta: false },
+  { fromLang: "en", toLang: "uk", isBeta: true },
+  { fromLang: "uk", toLang: "en", isBeta: true },
+];