Thunderbird

Opening Signature Settings

1. Open Thunderbird
2. Click the hamburger menu (☰) in the top-right corner
3. Go to Account Settings
4. Select the email account you want to add the signature to

Alternatively, right-click your account name in the left sidebar and select Settings.

Method 1: Paste HTML Directly

1. In the account settings, find the Signature text section
2. Check the box Use HTML
3. Click inside the signature editor
4. Paste your signature with Ctrl + V (or Cmd + V on macOS)

If the pasted content shows raw HTML tags instead of formatted content, use Method 2 instead.

Method 2: Use an HTML File

This method gives the most reliable results:

1. Open a text editor (e.g. Notepad, VS Code, or TextEdit in plain text mode)
2. Paste your copied signature HTML
3. Save the file as signature.html
4. In Thunderbird's account settings, check Attach the signature from a file instead
5. Click Choose... and select your signature.html file

Thunderbird will read the HTML file and render your signature with full formatting.

Setting Signature Position

Below the signature editor, you can configure:

• Attach this signature: choose when to include your signature
• Place my signature: select whether the signature goes below the quote or above it when replying

Troubleshooting

Signature shows HTML tags instead of formatted content

Make sure the Use HTML checkbox is enabled. If you're pasting and it still doesn't render, try Method 2 (file-based signature) for more reliable results.

Images don't appear in the signature

Thunderbird supports remote images in signatures, but some recipient email clients may block them. Make sure your image URLs are using HTTPS.

Signature appears twice

Check that you haven't set a signature in both the account settings and a Thunderbird identity. Go to Account Settings → Manage Identities and check each identity's signature settings.