[FR] - URL input field

[rickenella]

Describe the solution you'd like
It would be very practical if you could add an "URL field" to the "custom attributes". This could work in a similar way to this
example. Use "Right-Click" to edit the field.
(Since you can't upload .html, I used the .txt extension for the file.)

Describe alternatives you've considered
At the moment you could achieve this behavior using a HTML field, but that would be much more complex.