The page has a scrollbar but you don't know which element on page creates that scrollbar.
The Firefox Developer Tools allows us to see all elements causing overflow.
- In Firefox, open its Developer Tools
- Under the Inspector tab, if an element has a scrollbar (by using either
overflow: autobut the content is longer than the element dimension), it will be shown with a
In the following screenshot, the highlighted element is displayed with the
scroll badge indicating that it produces the scrollbar. Clicking the
scroll badge will reveal the associate element.