I would like to suggest some new function to What Nothing (Or a new extension) 🙂
It something like your Regular Labs - Extension Manager but it should work with all extension and the files can be uploaded from the a folder in the local computer.
So it will be basically like dragging all the update it to here:
We have many sites. Some of the extensions updates are not working directly with the online update option and we have to download it from the vendor and upload it to the server.
If I would have such an installer I will be able to update all the extension in one go...