Once Search highlights are given access for Windows 10, you can activate them by right-clicking the taskbar, selecting Search, and selecting the correct setting.
You could also switch it on or off using Windows registry in Windows 11 and Windows 10.
Right-click the Start button, select Run, and afterwards type regedit.exe into to the Run box.
Select New > Key from the menu by right-clicking the "Windows" folder. The new key's name is "Windows Search". Then, from the context menu, select New > DWORD value 32-bit by executing a right-click on "Windows search." "EnableDynamicContentInWSB" is the name of a 32-bit DWORD value. Double-click the "EnableDynamicContentInWSB" option and enter "1" to enable Search highlights or "0" to disable them.