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bug 32374) Heading dropdown disappears behind textarea after closing and re-opening the Advanced section. This seems to be caused by the collapsing animation that sets position:absolute on the section, does the fadeOut animation, then after the animation sets the position 'back' to relative. However, the position was never relative to begin with, so now the absolutely positioned header dropdown has a different closest positioned anchestor and it appears things go wrong from there and cause the bug. So instead of setting the position to relative after the animation, set it back to what it actually was before, which is static (implicitly).