overflow: scroll; other options for a scroll bar?

I have overflow: scroll; the only issue I am now getting is when I hover over a image and it expands in the css it only displays in the css box when I am using overflow:scroll; .. If I do not use overflow:scroll; then it displays out of the parent box. I have spent hours searching. But can not seem to find a solution. The pain is I still need the scroll but can't seem to find another solution. Anyone have any thoughts?

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