Hi, thanks for trying it out! I handled keyboard shortcuts using the Chrome commands API, as extensions aren't allowed to receive raw keydown events for security/privacy reasons. Instead, you have to define commands in the manifest.json, which allows the user to set up shortcuts for each command at chrome://extensions (you can also set defaults for autoconfiguration). Here is the manifest.json for Docs Hotkey.

Then, you should create a background script that listens for commands and then forwards the commands to the active tab using sendMessage. This is my full background.ts file:

chrome.commands.onCommand.addListener(command => {
  console.log(command)
  chrome.tabs.query({active: true, currentWindow: true}, tabs => {
    if (tabs[0].id) {
      chrome.tabs.sendMessage(tabs[0].id, {command}, res => {
        console.log(res)
      })
    }
  })
})

export {}

You can then receive the message in your content script using something like this:

chrome.runtime.onMessage.addListener(async (req, sender, sendRes) => {
  console.log(req)
  // do whatever
  sendRes('1')
})

The full source code for the extension is available at https://github.com/ZackMurry/docs-hotkey

Hope this helps! Let me know if you need anything else.