RTL Fixancer
RTL Fixancer is a private, per-site Chrome extension that improves Persian, Arabic, and Hebrew typography without sending page content anywhere.
Permissions and site activation (4.1.9)
Chrome receives HTTP/HTTPS host access once during installation or a version update, eliminating repeated Allow prompts when enabling new domains. Chrome may request approval for this new permission once.
- No static
<all_urls> content script.
- Broad host capability does not automatically process every website.
- Chrome site-access controls can still restrict individual sites.
- Content scripts are registered dynamically for enabled hostnames.
- Only the top frame is processed.
- One event-driven
MutationObserver replaces recurring DOM polling.
- Every changed attribute is captured and restored when the site is disabled.
- Legacy patch files and runtime monkey-patching have been removed.
- Print / Save as PDF uses the browser's native print flow and no longer scrolls through infinite pages.
Features
- Persian, Arabic, and Hebrew detection.
- Safe handling of mixed RTL/LTR text.
- Vazir, Shabnam, or the website's own font.
- Adjustable font size and detection sensitivity.
- Per-site activation and enabled-site management without repeated Chrome permission prompts.
- Site-agnostic detection: RTL text is found by its characters and its enclosing text block, not by per-site selectors, so it keeps working on ChatGPT, Grok, X, Gemini, AI Studio, Perplexity, DeepSeek and any other site after redesigns (open shadow roots included).
- Idle-time, time-budgeted processing that stays light during streaming chat responses.
- Code blocks and host navigation controls remain LTR.
- English and Persian popup UI.
Install for development
- Clone or download this repository.
- Open
chrome://extensions.
- Enable Developer mode.
- Select Load unpacked and choose the repository root.
- Open a normal HTTP/HTTPS page, click RTL Fixancer, and enable that site.
Chrome 120 or newer is required.
Verification
Node.js 22 or newer is required for repository checks.
npm run check
This runs manifest/source validation and the core unit tests. After runtime changes, also verify the extension manually in Chrome on a generic page and each supported AI chat UI.
Privacy and security
RTL Fixancer works locally. It does not include analytics, remote code, network APIs, or page-content uploads. Chrome grants broad HTTP/HTTPS host capability at installation (or after approving an update), but RTL Fixancer registers scripts only for hostnames explicitly enabled by the user. Chrome's own site-access controls remain available.
The only web-accessible files are the bundled Vazir and Shabnam font files.
Project structure
background.js Host-access checks, registrations, context menus, and icons
content.js Reversible, event-driven page runtime
lib/core.js Shared settings, domain, and language-detection logic
popup.html/css/js Accessible extension popup
scripts/validate.mjs Repository architecture and security validation
tests/ Node unit tests
docs/extension-audit.md Architecture and release verification notes
License
See LICENSE.
