Unchecked runtime.lastError: Could not establish connection. Receiving end does not exist.

needs to be handled in this way per https://stackoverflow.com/a/56787332

chrome.runtime.sendMessage('ping', response => {
    if(chrome.runtime.lastError) {
      // handle error
    } else {
      // handle response
    }
}

looks like firefox also puts the error on the port obj
https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime/Port

also looks like the error is handled more normally for some promise based apis, but likely not relevant to our usage of port
https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime/lastError