For websites, I use the Dark Reader extension, which does an incredible job turning any website into a dark version. https://chrome.google.com/webstore/detail/dark-reader/eimadp...

My main annoyance these days is that Office doesn’t let you invert the colors of a document as a display option. You have to actually change the background and text colors of the document.

I wish operating systems had a feature to invert the colors in a single window/app, as a fallback for when an application doesn’t have a dark mode.