I have tested Safari, Chrome and Firefox. This bug appears to only be present in Safari.
When you resize window by pulling up vertically, when you try to pull back down again…
The content doesn’t snap back down, and you have to reload the page. I never noticed before since I’ve generally used Firefox, but it’s just the browser that happened to be open today.
I did not test this with other versions of Safari. I did not test this with other lessons(because I’m lazy) than the ones depicted above.
Safari version: 12.1