Unable to add parameters to mailto links

[phette23]

Issue Summary

Using the rich text editor, you cannot add additional URI parameters to a mailto link such as subject, bcc, cc, etc. You can only pass a single email address.

Steps to Reproduce

1. Create a page or other model with a rich text field, then edit an instance of it
2. Add text, then hyperlink it
3. Try to add an email link with additional parameters e.g. help@example.com?subject=Help+Me or help@example.com?cc=support@example.com
4. You're told the email is invalid
5. You're also unable to add an analogous URI but with the "mailto:" scheme under External Link

I think the solution could be to validate not against an email address, but a mailto URI. I looked at the Draftail repo first but decided to open the issue here, since it seems that the link selection dialog is native to Wagtail and not the editor itself; forgive me if I'm wrong about that.

Any other relevant information. For example, why do you consider this a bug and what did you expect to happen instead?

• I have confirmed that this issue can be reproduced as described on a fresh Wagtail project: (yes / no)

No, but we are on the latest release (2.8).

Technical details

• Python version: 3.5.2
• Django version: 2.2.11
• Wagtail version: 2.8
• Browser version: Chrome 80

[gasman]

Hi @phette23 - thanks for the suggestion. A potential issue with having users enter mailto: links is that editor-level users are not necessarily technical, and may not know how to construct them. I think the way forward would be to have a separate optional field for subject / cc in the link chooser, which would then store the link internally as something like <a linktype="email" email="foo@example.com" subject="Help me"> - we can then use the existing link-rewriting logic (as used for page and document links) to convert this into a working mailto: URL.

[lb-]

PR raised a while ago with a partial solution - would be good if anyone is keen to pick that up and redo on the latest code + fix one of the minor feedback items.

#6451

[lb-]

#10920 has implemented the subject/body request in this issue, we will close when merged.

If support for cc/bcc is still requested, that can be requested as a future enhancement issue, it will likely involve a bit of InlinePanel to allow for multiple adding/re-ordering of a CC and/or BCC address.