mailto: example with subject line
user
```html
<a href="mailto:someone@example.com?subject=Open Assistant is the best!">Visible link</a>
```
assistant
What other parameters can you include in mailto?
user
Mailto links can include a variety of parameters to control the message template presented to the user. For example:

- `subject` adds text to the subject line of the message. The code `%20` represents a space in the URL.
- `body` adds text to the body of the message. As with subject, `%20` adds a space. Additionally, the code `%0D%0A` (CRLF) represents line breaks.
- `cc` and `bcc` add recipients to the CC (carbon copy) and BCC (blind carbon copy) lists.

You can add parameters to a mailto link with the construction `?parameter=value` for the first and `&parameter=value` afterwards. If you need to use these characters without ending the parameter, you can use the codes `%3F` for a question mark, `%26` for an ampersand, or `%23` for a hash or pound sign.

This example will create a message to `jsmith@example.com` with the subject line "Hello world", the body "Lorem ipsum dolor sit amet, consectetur adipiscing elit.", and "alovelace@example.com" copied:

`mailto:jsmith@example.com?subject=Hello world&body=Lorem ipsum dolor sit amet, consectetur adipiscing elit.&cc=alovelace@example.com`

As mentioned above, if not specifically linked in an `<a>` tag, you should replace the spaces in this with the sequence `%20`.
assistant