As someone who is constantly switching between dark and light modes, mapping ⌃ ⌃ to Toggle System Appearance in @raycast.com has been a game changer! Can't live without it now 🙏 Also, having worked on Arc and Dia, using ⌘ ⇧ C to copy the current url in my browser has been ingrained into my fingers.
I used @raycast.com to map that shortcut to a custom script that copies the current url from any browser I'm using. Legendary!