- Undo to reselect the light?
- Make temporary Outliner filter by writing the name of the asset you are looking for into Search bar
- Use folders to keep Outliner tidy.
- Use shift+click on the little arrow before folder/levelName icon (Outliner) to close/open all sub-folders recursively.
- Sort assests into several files and load them as sub-levels (Window/Levels). You can lock each sub-level to prevent its content from being selected (lock icon)