Expected effect: Your machine should freeze within ~30s to a minute; if not, your browser (or system) should kill the page and/browser to prevent a total lock up. This is different from the clone crash method, which only locks up your browser.
This is a test of a RAM crash vulnerability in the Scratch engine, which can potentially be used to prevent reporting, remixing, and such. Note that this loads your RAM very quickly, so your system may detect this easilly. For Scratch discussions