SendToBackground Not working in Content Script

[captDaylight]

In my content script I'm doing something like :

const res = await sendToBackground({
  name: 'ping',
  body: { test: 123 },
  extensionId: 'pfkngmdibomfbaoecnppfpmbepkbedkf'
});

But my messages/ping.ts isn't responding. However, if I do this in my popup.ts:

const res = await sendToBackground({
  name: 'ping',
  body: { test: 123 }
});

Then, I can detect the ping message. I'm not seeing any error if I try catch in the content script sendToBackground... am I missing something?