I seem to have found a bug with blocks which makes them duplicate constantly.
I added the Web_API1.Get block into the Screen1.Starts event.
Then I dragged the response block out of its default socket. (Another one appears in its previous place)
Drag the grayed-out block back onto the response output.
You can see that there are now 2 response blocks that are both grayed-out, and when I right click on block editor, the context menu says “Delete 353 blocks”. This number increases every time I right click to open the context menu again.
I know this isn’t just a bug with the context menu reporting the wrong number, because the blocks editor gets extremely slow, you can also see them disappear after clicking delete.