Add new item to the end of ordered multiselect instead of beginning

[dwbutler]

I'm using the filtering multiselect in a nested form with orderable: true. For our use case, it is very important that elements are always in the right order.

I noticed that when you create a new item, visually the new <option> appears to be added as the last child of the <select>. But when the form is submitted to Rails, the new IDs have actually been inserted at the beginning instead of at the end.

I finally tracked this down to a hidden <select> which is the real one submitted via Ajax. Changing prepend to append fixed the issue, causing new <option>s to be inserted at the end of the hidden <select>.

I would be happy to write some specs, but I couldn't find any existing specs for the multiselect widget. Maybe I just need to be pointed to the right file or create a new one.

[luizpicolo]

👍

[dwbutler]

@sferik Anything blocking this from getting merged?

[mshibuya]

Merging in, thanks!

[dwbutler]

@mshibuya Awesome, thanks!