Why is ngrok url refusing to connect during app development?

[tzahisofer]

Hi,

I am building my first app and followed the Getting Started guide.

I am currently stuck after "shopify app serve" command: the command itself is successful (I get the "Ready on http://localhost:8081| message), but trying to navigate to the ngrok url provided hits a "refused to connect" message in the browser. 

As mentioned in similar posts, I don't see any cookies issue.

Any idea anyone?

tnx