Feature request or help needed for modal close confirmation popup

[teknofi]

I can't currently see a way to show a confirmation message when a modal is closed either through the close button or by clicking off a modal where a confirmation box is shown where the user has input data on a create form but hasn't saved that data. It would be nice to display something like:

"Are you sure you want to close this form, input data will be lost" with a yes no prompt

is this currently achievable and if not can you add it to the improvement suggestions?