Add hidden submit button

[jimchamp]

Closes #6471

Adds a hidden submit button prior to the "Delete" submit button.

Technical

A form's first submit button is triggered when enter is pressed. PR #6273 linked the previously broken top-of-page delete button to the form, making it the form's first submit button.

Testing

Screenshot

Stakeholders

[cdrini]

Yep; can't find a better solution. Because the consequences of this are a little extreme, let's see if we can avoid this happening in the future!

Could you (1) create a $def like render_submit_button(hidden=False), so that the two submit buttons always have the correct values? I.e. DRY up their rendering logic. No need for this to be a separate file of course!

And (2) try placing the hidden button as the first element in the addWork <form>. That should hopefully prevent this issue from ever happening again!

[cdrini]

Oh, and (3) add a comment about why it's necessary; so some future person doesn't "helpfully" delete the "unused hidden button"

[cdrini]

This macro is referenced in a BUNCH of other places ; we can't modify it like this -- you know unless we do want to delete the Save button on every page but the book page :P It's a good idea to check for usages of a template/function whenever modifying its arguments. I'm going to roll back the last commit 👍

[cdrini]

Tested:

• ✅ Pressing enter saves for librarians and non-librarians (FF, Chrome, IE)
• ✅ Pressing delete deletes (FF, Chrome)
  • Doesn't work in IE, but since librarian only feature, doesn't need to be IE-compatible.

[cdrini]

@jimchamp The DRY-ing of the submit buttons doesn't appear to be worth it because there's another template in the way, so ignoring. I was able to move the submit button up to the top of the template. I missed that it wasn't inside the <form element, so it needs to be at the top outside the form element.