1 files changed, 62 insertions, 0 deletions
diff --git a/browser/components/customizableui/test/browser_1856572_ensure_Fluent_works_in_customizeMode.js b/browser/components/customizableui/test/browser_1856572_ensure_Fluent_works_in_customizeMode.js
new file mode 100644
index 0000000000..0f89bd5d1c
--- /dev/null
+++ b/browser/components/customizableui/test/browser_1856572_ensure_Fluent_works_in_customizeMode.js
@@ -0,0 +1,62 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+const {
+  openFirefoxViewTab,
+  withFirefoxView,
+  init: FirefoxViewTestUtilsInit,
+} = ChromeUtils.importESModule(
+  "resource://testing-common/FirefoxViewTestUtils.sys.mjs"
+);
+
+add_task(async function test_data_l10n_customize_mode() {
+  FirefoxViewTestUtilsInit(this);
+  await withFirefoxView({ win: window }, async function (browser) {
+    /**
+     * Bug 1856572, Bug 1857622: Without requesting two animation frames
+     * the "missing Fluent strings" issue will not reproduce.
+     */
+    await new Promise(r =>
+      requestAnimationFrame(() => requestAnimationFrame(r))
+    );
+    await startCustomizing();
+    await endCustomizing();
+    await openFirefoxViewTab(window);
+
+    const { document } = browser.contentWindow;
+    let header = document.querySelector("h1");
+    document.l10n.setAttributes(header, "firefoxview-overview-header");
+    let previousText = await document.l10n.formatValue(
+      "firefoxview-page-title"
+    );
+    /**
+     * This should be replaced with
+     * BrowserTestUtils.waitForMutationCondition(header, {characterData: true}, ...)
+     * but apparently Fluent manipulation of textContent doesn't result
+     * in a characterData mutation occurring.
+     */
+    await BrowserTestUtils.waitForCondition(() => {
+      return header.textContent != previousText;
+    }, "waiting for text content to change");
+
+    Assert.equal(
+      header.getAttribute("data-l10n-id"),
+      "firefoxview-overview-header",
+      "data-l10n-id should be updated"
+    );
+    Assert.notEqual(
+      previousText,
+      header.textContent,
+      "The header's text content should be updated"
+    );
+    let translatedText = await window.content.document.l10n.formatValue(
+      "firefoxview-overview-header"
+    );
+    Assert.equal(
+      translatedText,
+      header.textContent,
+      "The changed text should be the translated value of 'firefoxview-overview-header"
+    );
+  });
+});