| Clue | Source | Date |
|---|---|---|
| Smartphone setting that may help reduce screen time | LA Times Daily | 03 Dec 2022 |
| Colorless mode at a copy shop | New York Times | 31 Mar 2019 |
| It varies from black to white | New York Times | 13 Mar 2019 |
| Colorless mode at a copy shop | ||
| It varies from black to white |