It might be a bit trickier, because if you hardcode the port in the manifest, the user wouldn't be able to change it? Might be better than nothing I guess, but

It might be a bit trickier, because if you hardcode the port in the manifest, the user wouldn't be able to change it? Might be better than nothing I guess, but on the long term you'd need to add the port in settings and request the permission for localhost+port dynamically? But that's got another issue, e.g. last time I tried it [0] for my extension, Firefox didn't support dynamic URL permissions for URLs with ports. [0] https://github.com/karlicoss/grasp/blob/f24378ebae68c22bea03e72fa8cfc6da777adcb0/src/js/permissions.js#L15-L24 https://github.com/karlicoss/grasp/blob/f24378ebae68c22bea03...