After using Prepare to Search or pressing Ctrl+F and entering a search term, click the Highlight button on the Search toolbar or select the Highlight All item in the Search menu to turn on the search match highlighting mode. In this mode, all search matches will be highlighted. The Selection Only option is ignored.
When you switch between files, search matches in the newly activated line are highlighted. The “all files“ setting does not affect match highlighting. To stop highlighting search matches, simply click the Highlight button again.
To change the color or underlining style used for highlighting search matches, customize the color palette and change the “Editor: Highlighted search match” color.
Search menu
Search|Prepare to Search
Search|Search Options
Search|Instant Highlight