There should be some CSS rules to limit the size of auto-complete suggestions in mentions panel view:

鈽濓笍 With maximum height of a panel, we should add here overscroll-behaviour: contain support.
I think we should also recommend to return a .slice( 0, 10 ) in the feed callback. There's no point to render 10000 results for a generic query.
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I think we should also recommend to return a
.slice( 0, 10 )in the feed callback. There's no point to render 10000 results for a generic query.