Other parts of the JS performance scroll bar

Problem:

If a page has a large aspect ratio, that is, the page needs a scroll bar to view the contents of the other pages, the rest of the scroll bar is still in the running state.

For example, that part of the video playback, but those videos are not visible in the current window, but they will still be in the playback state, that is, in the constant consumption of resources on the page!

Workaround:

# If the page does not have scroll bars, that is, a page can fully display all the content, there is no need to solve the problem.

1 Write a function, specifically for listening to all the content of the page, if a module is outside the scroll bar, the module is hidden operation--display:none;