Latex It!

Description

This extension runs local latex and dvipng binaries to convert $...$ and $$...$$ expressions into inline images while composing HTML emails in Thunderbird.

The add-on now uses the MailExtension + Experiment API model and targets Thunderbird 140+.

Features

• Run LaTeX conversion on all matching expressions in a compose window
• Undo / undo all inserted images
• Insert complex LaTeX at cursor position
• Configure executable paths, template, DPI behavior, and debug/log options
• Auto-detect latex and dvipng in your PATH
• Auto-fallback to local helper service for sandboxed Thunderbird installs

Requirements

• Thunderbird 140 or newer
• A local TeX setup with:
  • latex
  • dvipng
• For sandboxed Thunderbird (Snap/Flatpak), use the local helper service. Preferred on Linux: install it as a systemd --user service.

Build

Run:

make

This produces tblatex.xpi.

Install

1. Build the extension:

make

2. In Thunderbird, open Add-ons and Themes.
3. Click the gear icon and choose Install Add-on From File....
4. Select tblatex.xpi.
5. Open LaTeX It! options and confirm latex / dvipng paths (or click autodetect).
6. If Thunderbird is sandboxed, enable helper fallback in options and make sure helper URL matches your helper service.

Publishing a fork on ATN

If you are publishing your own fork (not updating the original add-on listing), build with a unique add-on ID:

make ADDON_ID='tblatex@your-domain-or-handle.example' OUT='tblatex-fork.xpi'

Upload tblatex-fork.xpi to ATN. This avoids "Duplicate add-on ID found."

Development install (temporary)

1. In Thunderbird, open Tools -> Developer Tools -> Debug Add-ons.
2. Click Load Temporary Add-on....
3. Select this repository's manifest.json.

Usage Notes

• Conversion works in HTML compose mode.
• In a compose window, use the LaTeX It! compose action menu and click Run LaTeX in body.
• This converts expressions like $\frac{2}{3}$ and $$\boxed{\frac{34}{31}}$$ into inline PNG images.
• Default shortcut for silent conversion: Ctrl+Shift+L (Cmd+Shift+L on macOS).

Sandbox Fallback (Snap/Flatpak)

Primary option (Linux): install helper as a user service

bash helper/install-systemd-user.sh

Fallback option: run helper manually

python3 helper/tblatex_helper.py

Then in extension options:

• Enable local helper fallback.
• Set helper URL to http://127.0.0.1:3737 (or your custom host/port).
• Click Test helper.

When direct binary execution is blocked by sandboxing, LaTeX It! will automatically route rendering through the helper.