If nothing weird happens, reload
I've used a modified version of the technique that I've seen at https://scratch.mit.edu/discuss/topic/875554/ How does this work? Scratch temporarily inserts the vector costumes into the DOM while loading them, and this applies their CSS to the page for less than 1 frame. @fortyonegames discovered that it's possible to make the CSS stay applied for a longer time. The way this works is that there are two costumes, one that has applies some CSS styles to the page, and one that adds long CSS transitions for those styles. This makes the browser start a long transition from the costume's CSS to Scratch's default CSS when Scratch replaces the first costume with the second costume in the DOM, and it seems like the browser doesn't stop doing the transitions* when the CSS that asked the transition is removed. * For some reason, my browser only continues doing the transitions on elements that also have transitions in Scratch's CSS, but it continues doing the long transitions even though Scratch's CSS asks only some short transitions. Because of this, I only see 1 banana, unless I pause Scratch in the DevTools before it removes the costume that asks the long transitions
