Unfortunately it is deliberate. As a Caltech student I told them not to do this, but they thought it was edgy and hip.
1
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[4========]
4 is hidden by a fixed footer. When it pages up the next page is: 5
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[8========]
and you've missed out on all the section 4 and 8 content.So it's rather the facility of skipping by screenfuls of content rather than the key itself.