I'm probably the only person who didn't know about this feature...
but there appears to be 2 different bulk image uploaded options.
I've seen this one before... when you select image / assets tab and drag an image onto the platform:
But this is the first time I've seen this one... (not really sure how I did it though)
Drag again onto the Designer... and he get this:
(Like me... ) If you didn't... well know you do.