Doesn’t seem fixed to me. Also, it’s impossible to fix it in the current structure without JavaScript, because you need to either move the caret into the desired scrolling element (`getSelection().collapse(document.querySelector('.main'))`), or focus it (`document.querySelector('.main').focus()`, also requiring tabindex=-1 or similar on the element). From the presence of tabindex=1 on .main, I’m guessing you tried that one.

For a documentation thing like this, I’d generally recommend avoiding a separate scrolling pane for the primary content, but rather arranging so that it can use the document’s scrolling element. This gets the scrollbar in the place people generally expect it in web things, and makes it work regardless of whether the JS loads.