It does, it just doesn’t auto pause it by default when the window is closed. But there is nothing stopping a designer from applying something to handle that all within Blocs using a 3rd party solution.
Some videos may be youtube, vimeo, local or some other platform and most require different solutions to auto pause when a modal is closed. Some modals may contain videos some may not, so with all of this in mind, what Im trying to say is there is no efficient feature I can add to efficiently handle this. It’s best that the designers decides on the solution and uses, page attachments (for JS), custom data attributes and ID’s (for binding) to implement it.