"Use as exit node" button disabled in dashboard - why?

Hi there!

Attempting to try the exit node feature, the “use as exit node” button/switch is disabled in the dashboard. I can’t figure out why - I’ve read the instructions several times and don’t see a step I’m missing. Here’s what it looks like:

Hovering over the switch on desktop shows a “disabled” cursor; it is not clickable.

As a feature request, it would be awesome if the dashboard can tell me why this node isn’t eligible to be an exit node, since it seems to be making that decision somewhere. As it stands - I’m stuck. Thanks!

Tailscale version: 1.26.2
Your operating system & version: MacOS (desktop), Ubuntu (device)

Well, I feel dumb… sortof. There is an explanation in the dashboard, but it seems to only show if you mouseOver. I was on a mobile device. Doh.

Suggestion: This hint isn’t mentioned in the docs; please add it to the prerequisites section!