Form inputs inside sortable elements (like variations) don't work on mobile

[adamjudd]

For aspects that we support as sortable, such as product variations, when on mobile it's not possible to interact with the form inputs within the sortable element.

If you click the label, it will focus the form element, but you can't directly interact with the input/textarea/select.

This appears to be a bug with the jQuery UI sortable plugin when jQuery Touch Punch is also included on the page, but from a quick search I can't see a clear solution to the direct issue. One approach we could take is to introduce a handle that is used for sorting, rather than just using the whole element as a handle. It means that people need to be more deliberate about where they grab - but would fix this issue.