Chrome still ships no dark mode for its built-in PDF viewer. Open a white paper at 1am and you get a flashbang. So you go to the Web Store, install the extension with the most installs, click it, and… nothing happens.
Source: [Dev.to](https://dev.to/liuhao04/why-most-pdf-dark-mode-chrome-extensions-do-nothing-on-a-web-pdf-on5)