You are trying to adapt a pop up of the system (e.g. a value help, add products screen, etc.), but when you open this pop up, even though you are in Adaptation Mode, the options to adapt are not highlighted.
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Even though the pop up is open, it is not selected yet and below screen remains active.
To make the adapt options appear you need to just perform a click or right-click with your mouse cursor on the pop up window, so the browser selects it as the active screen. The Adapt options will then show up.
Adaptation; Pop Up; Highlight; Active; Flexibility; , KBA , AP-RC-UIF-FLX , Page Layout & Key User Configuration , How To