While you can turn any text or image into any link "manually" (to link to an email address, use "mailto:somebody@example.com" for the link address) in an email you compose in Mozilla Thunderbird, you often do not have to. Mozilla Thunderbird turns email addresses and addresses of web pages into clickable links automatically.
Mozilla Thunderbird Turns Email Addresses and URLs into Links Automatically
To insert a clickable email address link in an email:
- Type the email address, "somebody@example.com", for example.
To insert a clickable link to a page on the web:
- Type or paste the address from the browser's address bar, "http://email.about.com/", for example.
If your message is sent using HTML formatting, Mozilla Thunderbird will automatically add the clickable links. In the plain text version, the URLs and email addresses will remain untouched as this is the right thing to do. The recipient's email program will typically turn these addresses into usable links.
(Updated May 2012)

