If you open the embed page for any project, and click escape on your keyboard, it gets messed up.
Open any project's embed page (scratch.mit.edu/{projectid}/embed) and click escape on your keyboard. See that it gets small, and is glitched out.

This probably roots back to how the embed page was created from the typical fullscreen page.
ChromeOS
I've reproduced this on Mac Chrome, Firefox, and Safari.
Occurs also in an iframe (i.e.
data:text/html,<iframe width="560" height="480" src="https://scratch.mit.edu/projects/{projectid}/embed"/>
for a simple test)
Intresting. Also a more professional embed page would be nice, less original white space and an automatically starting project.
@Explosion-Scratch Auto-starting does not work well on some browsers (particularly Chrome - sounds won't play without user interaction)
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