<p>I've been able to reproduce this issue, both on Firefox (Ubuntu desktop) and Safari (iOS).</p>
<p>The problem is when both the <code>sidebar</code> (normally on the left in full size version) and the <code>map-ui</code> (normally on the right) panels are open at the same time, then the lower <code>map-ui</code> panel can't be completely scrolled. This happens with any combination of the two panel types. For example, with your browser narrow enough to trigger the small screen css, open the "New Note" panel (<code>sidebar</code>) and the Legend (<code>map-ui</code>). The legend panel can be scrolled but not all the way to the bottom. Other combinations (like search results in <code>sidebar</code> and layer switcher in <code>map-ui</code>) also show the same behaviour. If only one of the two panels is open, scrolling works fine for both panel types.</p>

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