v0.5.2

Allow close on Esc even if role="alertdialog" as per wai-aria guideline example

Note that backdrop click to close is still prevented, because technically it's outside the dialog element (and we haven't tested another way so), probably in the next release we'll have smarter prevention.

Content authors SHOULD make alert dialogs modal by ensuring that, while the alertdialog is shown, keyboard and mouse interactions only operate within the dialog.
https://www.w3.org/TR/wai-aria-1.1/#alertdialog