Detect CSS Overflow Elements

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Every once in a while you encounter a CSS annoyance that takes some cleverness to discover. One such case rears its ugly head in unwanted and unexpected scrollbars. When I see unwanted scrollbars, I usually open developer tools, click the element inspector, and hover around until I find the villainous HTML element. As a visual person, I find that process effective but not efficient. Recently I was made aware of a programmatic way to find the scoundrel element with JavaScript!

To find the element summoning demon scrollbars, you can use the following JavaScript:

document.querySelectorAll('*').forEach(el => {
  if (el.offsetWidth > document.documentElement.offsetWidth) {
      console.log('Found the worst element ever: ', el);
  }
});

After the element has been logged to the console, you can pinpoint it and play with punishments in the element inspector as you see fit.

I'm always guilty of reverting to my old ways, i.e. visual inspection, but having a programmatic solution is so much faster and convenient!

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Discussion

  1. Craig

    Great little script… To make it easy to use, I ended up creating a Bookmarklet with a slightly modified version of that script. Then I can run it easily on any page.

  2. Gregor

    Firefox Developer edition (not sure about the normal one) also has an indicator on the HTML element that is causing the overflow

  3. Sagive

    Still didn’t help me to find the colporate for some reason… also tried the * {border: 1px solid red} trick to try to identify whats happening (tears!) – ended up just overflow-x hidden – which is lazy i guess

    But.. thanks for sharing. gr8 logic that little script

    • Sean

      I’m not sure it will help in your particular case, using outline instead of border can be a good shout, it won’t add to the width of elements (when border-box is not used)

  4. Antonio

    Maybe you want to say…

    if (el.scrollWidth > document.documentElement.offsetWidth)
    

    Thanks for sharing

  5. Antonio

    But you must to take account of margins, etc.

  6. Antonio

    This line works better for me:

    if (el.scrollWidth > el.clientWidth)
    

    Detection includes cases where no scrollbar is showed but something wrong is happening.

    Thanks David for inspiring us.

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