Problems with HTML5 flexible box model

Question

So I have this code: https://code.sololearn.com/Wty08V2PCN31
Whenever I run that code on my browser (Chrome 70) the aside element appears under article but when I run it on Sololearn the article element is next to the aside element. Why is that happening?

Answer 1

I don't know the reason, but if you change the closing </div> tag from line 46 to line 43 (put it behind the closing </section> tag in line 42) it will work on SoloLearn app too. (I'm not sure the aside tag is in good place in 'new_div'. Maybe this 'new_div' id style content is incomplete or defective.)