Wizard Step 1: Deleting Webinar URL results in error "not valid URL"

[mariobehling]

It seems it is not possible to delete a webinar or live stream URL. When an organizer tries to delete it and hits "Save" an error message "Not a valid URL" shows up.

Expected: It should be possible to delete these URLS as the field is not required.

Compare https://eventyay.com/events/fa96ae2c/edit/basic-details

[maze-runnar]

looking into it