How to access micro8ks's dashboard web UI?

The information is well hidden in microk8s.kubectl get all --all-namespaces, maybe elsewhere. Since kubectl not well documented and not intuitive at all, I recommend

microk8s.kubectl get all --all-namespaces | grep service/kubernetes-dashboard

which reveals an IP address which you need to access with https:// prefixed in your browser because there's no redirect from HTTP to HTTPS.

I just use

microk8s dashboard-proxy

which results in

Checking if Dashboard is running.
Dashboard will be available at https://127.0.0.1:10443
Use the following token to login:
eyJhbGciOiJSUzI1NiIsImtpZCI6ImJVTm01V1dBSHJUQVNtenFrRHExRWFPakd4X090QzVYQkcxUmRvdkItaUUifQ.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJkZWZhdWx0LXRva2VuLXprdmQ5Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZXJ2aWNlLWFjY291bnQubmFtZSI6ImRlZmF1bHQiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiJhMDVlZmFkNS03MzE1LTRiYzctOTk4OC04ZDg5YzA0YmU0YjIiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6a3ViZS1zeXN0ZW06ZGVmYXVsdCJ9.Oqqkn5hQoaWqwE6puYgrcWKKVzEwO49JZYWntXEnx2hycIlyhfbWWLPoJmboRMh4Ox85eZsuPmd9BuHLC9MfbR62XlXaEQlE3Pc-G9J7nR-eekXJaN6xVQWrL-uKNG5mnoPAFpD0LskdHTrlX1BL3zLRoX2LGRlk2xozNjlOwDpnJmhHR8u7naWxb-YZBeRov757GJNu7n2N5iysba5tyf3X_NkNyTl9sjmiUGIo9o2xIujWPxmlpbqvUP5wcEEf9z6oIUjWP78WCZPl9RvpHU3o1lKe2WwC_PKZQga5qATuLJfv1L0hhOFOeuui70c2L0bUuozfMlEw77AIpALwGg

It works in Firefox without issues. For Google Chrome I had to enable the flag allow-insecure-localhost to allow local websites without correct security. This is done by opening chrome://flags/#allow-insecure-localhost and enabling the flag as shown: