Safari on iOS has an issue with :hover. If you apply :hover to a non-link that contains a link and also shows or hides and other element then you must twice to navigate. The first applies the changes for :hover while the second Actually does the navigation.
These work because there is only a color change.
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Font-size Peekaboo!
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Color Peekaboo!
These don't work because an element is being hidden or displayed.
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Visilibity Peekaboo!
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Display Peekaboo!