firefox上pdf的黑色模式

1. Open Firefox and press Alt to show the top menu, then click on Help → Troubleshooting Information
2. Click the Open Directory button beside the Profile Directory entry
3. Create a folder named chrome in the directory that opens
4. In the chrome folder, create a CSS file with the name userContent.css
5. Open the userContent.css file and insert -

#viewerContainer > #viewer > .page > .canvasWrapper > canvas {
	filter: grayscale(100%);
	filter: invert(100%);
}

6. On Firefox's URL bar, type about:config.
7. Search for toolkit.legacyUserProfileCustomizations.stylesheets and set it to true.
8. Restart Firefox and fire up a PDF file to see the change!

Dark mode for Firefox's built-in PDF viewer