@Marostegui Thanks! It looks it working so I went ahead and removed the old key in T283940.

In T274263#6925182, @DLynch wrote:

For what it's worth, you shouldn't need to do any direct work to add a button. There's already code for having a standardized delete button on context items, it's just restricted to the MobileContext. If you look up ve.ui.MobileContext.static.showDeleteButton you can trace through how its display is triggered.

It'd be really easy to go big and just enable delete buttons on all non-mobile context items.

It'd also be simple to just override isDeletable on MWTransclusionContextItem -- check out TableContextItem for an example. So long as that's returning true, a delete button will show.

Watch out for paramOrder (https://www.mediawiki.org/wiki/Help:TemplateData#Required_property_%22paramOrder(number)%22_not_found)

Moved to T274550 and T274545