zen-browser · mbergo · Jul 15, 2025
diff --git a/src/zen/browser/base/content/ZenCyrillicEncodingFix.sys.mjs b/src/zen/browser/base/content/ZenCyrillicEncodingFix.sys.mjs
@@ -0,0 +1,44 @@
+/* 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/. */
+
+export const ZenCyrillicEncodingFix = {
+  // Cyrillic character range detection
+  CYRILLIC_REGEX: /[\u0400-\u04FF]/,
+
+  init() {
+    // Listen for form submissions
+    Services.obs.addObserver(this, 'earlyformsubmit');
+  },
+
+  observe(subject, topic, data) {
+    if (topic === 'earlyformsubmit') {
+      this.handleFormSubmission(subject);
+    }
+  },
+
+  handleFormSubmission(form) {
+    // Apply fix to all sites with Cyrillic content
+    this.fixCyrillicEncoding(form);
+  },
+
+  fixCyrillicEncoding(form) {
+    const inputs = form.querySelectorAll('input[type="text"], input[type="search"], textarea');
+
+    for (const input of inputs) {
+      if (this.CYRILLIC_REGEX.test(input.value)) {
+        // Ensure proper UTF-8 encoding for Cyrillic characters
+        input.setAttribute('accept-charset', 'UTF-8');
+
+        // Force the form to use UTF-8 encoding
+        if (form.acceptCharset !== 'UTF-8') {
+          form.acceptCharset = 'UTF-8';
+        }
+      }
+    }
+  },
+
+  uninit() {
+    Services.obs.removeObserver(this, 'earlyformsubmit');
+  },
+};
diff --git a/src/zen/browser/base/content/zen-browser.js b/src/zen/browser/base/content/zen-browser.js
@@ -0,0 +1,5 @@
+// Add this import at the top with other imports
+import { ZenCyrillicEncodingFix } from './ZenCyrillicEncodingFix.sys.mjs';
+
+// Add this in the initialization section
+ZenCyrillicEncodingFix.init();
diff --git a/src/zen/tests/localization/browser.toml b/src/zen/tests/localization/browser.toml
@@ -0,0 +1,6 @@
+[DEFAULT]
+support-files = [
+  "head.js",
+]
+
+["browser_cyrillic_encoding_fix.js"]
diff --git a/src/zen/tests/localization/browser_cyrillic_encoding_fix.js b/src/zen/tests/localization/browser_cyrillic_encoding_fix.js
@@ -0,0 +1,207 @@
+/* Any copyright is dedicated to the Public Domain.
+   https://creativecommons.org/publicdomain/zero/1.0/ */
+
+'use strict';
+
+const { ZenCyrillicEncodingFix } = ChromeUtils.importESModule(
+  'resource:///modules/ZenCyrillicEncodingFix.sys.mjs'
+);
+
+add_task(async function test_cyrillic_encoding_fix_known_sites() {
+  // Test on the originally problematic sites
+  await testCyrillicEncodingOnSite('https://nnmclub.to/forum/search.php');
+  await testCyrillicEncodingOnSite('https://4pda.to/search/');
+});
+
+add_task(async function test_cyrillic_encoding_fix_any_site() {
+  // Test that the fix works on any website with Cyrillic content
+  await testCyrillicEncodingOnSite('https://example.com/search');
+  await testCyrillicEncodingOnSite('https://test-site.ru/form');
+  await testCyrillicEncodingOnSite('https://random-site.org/contact');
+});
+
+add_task(async function test_cyrillic_regex_detection() {
+  // Test Cyrillic character detection
+  ok(ZenCyrillicEncodingFix.CYRILLIC_REGEX.test('Привет'), 'Should detect Cyrillic characters');
+  ok(ZenCyrillicEncodingFix.CYRILLIC_REGEX.test('Тест'), 'Should detect Cyrillic characters');
+  ok(ZenCyrillicEncodingFix.CYRILLIC_REGEX.test('Поиск'), 'Should detect Cyrillic characters');
+  ok(ZenCyrillicEncodingFix.CYRILLIC_REGEX.test('Москва'), 'Should detect Cyrillic characters');
+  ok(!ZenCyrillicEncodingFix.CYRILLIC_REGEX.test('Hello'), 'Should not detect Latin characters');
+  ok(!ZenCyrillicEncodingFix.CYRILLIC_REGEX.test('123'), 'Should not detect numbers');
+  ok(!ZenCyrillicEncodingFix.CYRILLIC_REGEX.test(''), 'Should not detect empty string');
+});
+
+async function testCyrillicEncodingOnSite(url) {
+  // Create a mock HTML page with a search form
+  const mockHTML = `
+    <!DOCTYPE html>
+    <html>
+    <head>
+      <meta charset="windows-1251">
+      <title>Test Page</title>
+    </head>
+    <body>
+      <form id="searchForm" method="post" action="/search">
+        <input type="text" id="searchInput" name="query" value="">
+        <textarea id="textArea" name="description"></textarea>
+        <input type="search" id="searchField" name="search" value="">
+        <input type="submit" value="Search">
+      </form>
+    </body>
+    </html>
+  `;
+
+  await BrowserTestUtils.withNewTab({ gBrowser, url: 'about:blank' }, async (browser) => {
+    // Load the mock HTML
+    await SpecialPowers.spawn(browser, [mockHTML, url], async (html, testUrl) => {
+      // Set the document URI to simulate being on any site
+      Object.defineProperty(content.document, 'documentURI', {
+        value: testUrl,
+        writable: false,
+      });
+
+      content.document.documentElement.innerHTML = html;
+    });
+
+    // Test Cyrillic input handling
+    await SpecialPowers.spawn(browser, [], async () => {
+      const form = content.document.getElementById('searchForm');
+      const input = content.document.getElementById('searchInput');
+      const textarea = content.document.getElementById('textArea');
+      const searchField = content.document.getElementById('searchField');
+
+      // Test different Cyrillic texts
+      const cyrillicTexts = ['Поиск тест', 'Привет мир', 'Русский текст'];
+
+      for (let i = 0; i < cyrillicTexts.length; i++) {
+        const cyrillicText = cyrillicTexts[i];
+
+        // Test input field
+        input.value = cyrillicText;
+        textarea.value = `Описание: ${cyrillicText}`;
+        searchField.value = cyrillicText;
+
+        // Trigger the form submission handler
+        const event = new content.Event('submit', { bubbles: true, cancelable: true });
+        form.dispatchEvent(event);
+
+        // Check if the encoding fix was applied
+        Assert.equal(
+          form.acceptCharset,
+          'UTF-8',
+          `Form should have UTF-8 accept-charset after Cyrillic input: ${cyrillicText}`
+        );
+        Assert.equal(
+          input.getAttribute('accept-charset'),
+          'UTF-8',
+          `Input should have UTF-8 accept-charset after Cyrillic input: ${cyrillicText}`
+        );
+        Assert.equal(
+          textarea.getAttribute('accept-charset'),
+          'UTF-8',
+          `Textarea should have UTF-8 accept-charset after Cyrillic input: ${cyrillicText}`
+        );
+        Assert.equal(
+          searchField.getAttribute('accept-charset'),
+          'UTF-8',
+          `Search field should have UTF-8 accept-charset after Cyrillic input: ${cyrillicText}`
+        );
+      }
+    });
+  });
+}
+
+add_task(async function test_non_cyrillic_input_unchanged() {
+  const mockHTML = `
+    <!DOCTYPE html>
+    <html>
+    <body>
+      <form id="testForm" method="post">
+        <input type="text" id="testInput" name="query" value="English text">
+        <input type="submit" value="Search">
+      </form>
+    </body>
+    </html>
+  `;
+
+  await BrowserTestUtils.withNewTab({ gBrowser, url: 'about:blank' }, async (browser) => {
+    await SpecialPowers.spawn(browser, [mockHTML], async (html) => {
+      // Set URI to any site (global fix should work everywhere)
+      Object.defineProperty(content.document, 'documentURI', {
+        value: 'https://example.com/search',
+        writable: false,
+      });
+
+      content.document.documentElement.innerHTML = html;
+
+      const form = content.document.getElementById('testForm');
+      const input = content.document.getElementById('testInput');
+
+      // Store original values
+      const originalAcceptCharset = form.acceptCharset;
+      const originalInputCharset = input.getAttribute('accept-charset');
+
+      // Trigger form submission with non-Cyrillic text
+      const event = new content.Event('submit', { bubbles: true, cancelable: true });
+      form.dispatchEvent(event);
+
+      // Verify that non-Cyrillic text doesn't trigger encoding changes
+      Assert.equal(
+        form.acceptCharset,
+        originalAcceptCharset,
+        'Form accept-charset should not change for non-Cyrillic text'
+      );
+      Assert.equal(
+        input.getAttribute('accept-charset'),
+        originalInputCharset,
+        'Input accept-charset should not change for non-Cyrillic text'
+      );
+    });
+  });
+});
+
+add_task(async function test_mixed_content_forms() {
+  const mockHTML = `
+    <!DOCTYPE html>
+    <html>
+    <body>
+      <form id="mixedForm" method="post">
+        <input type="text" id="englishInput" name="english" value="Hello">
+        <input type="text" id="cyrillicInput" name="cyrillic" value="Привет">
+        <input type="text" id="numberInput" name="numbers" value="12345">
+        <input type="submit" value="Submit">
+      </form>
+    </body>
+    </html>
+  `;
+
+  await BrowserTestUtils.withNewTab({ gBrowser, url: 'about:blank' }, async (browser) => {
+    await SpecialPowers.spawn(browser, [mockHTML], async (html) => {
+      Object.defineProperty(content.document, 'documentURI', {
+        value: 'https://mixed-content-site.com/form',
+        writable: false,
+      });
+
+      content.document.documentElement.innerHTML = html;
+
+      const form = content.document.getElementById('mixedForm');
+      const cyrillicInput = content.document.getElementById('cyrillicInput');
+
+      // Trigger form submission
+      const event = new content.Event('submit', { bubbles: true, cancelable: true });
+      form.dispatchEvent(event);
+
+      // Should apply UTF-8 encoding because one field contains Cyrillic
+      Assert.equal(
+        form.acceptCharset,
+        'UTF-8',
+        'Form should have UTF-8 accept-charset when any field contains Cyrillic'
+      );
+      Assert.equal(
+        cyrillicInput.getAttribute('accept-charset'),
+        'UTF-8',
+        'Cyrillic input should have UTF-8 accept-charset'
+      );
+    });
+  });
+});
diff --git a/src/zen/tests/localization/head.js b/src/zen/tests/localization/head.js
@@ -0,0 +1,5 @@
+/* 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/. */
+
+// Common utilities for localization tests
diff --git a/src/zen/tests/moz.build b/src/zen/tests/moz.build
@@ -6,6 +6,7 @@ BROWSER_CHROME_MANIFESTS += [
     "compact_mode/browser.toml",
     "container_essentials/browser.toml",
     "glance/browser.toml",
+    "localization/browser.toml",
     "pinned/browser.toml",
     "urlbar/browser.toml",
     "welcome/browser.toml",