Please note, I've now uploaded a list of the v1.0 HandyDash features to GitHub, also shown below. Thanks.

[Available Checks]
HTTP check for 200-299 (success) responses (follows 30X redirects).
HTTP check for specific response content (text).
HTTP check for latest and average response times.
HTTP check for validity of server, intermediate, and root certificates.
TCP check conducted (only) if HTTP check failure occurs.
IP check conducted (only) if TCP check failure occurs.

[Warnings & Failures]
Informative summary of HTTP, TCP, IP warnings and failures.
Warning if HTTP response is slower than average by 100%.
Warning if expiry date of server, intermediate, root certificate is less than 2 weeks, but more than 2 days.
Error if expiry date of server, intermediate, root certificate is less than 2 days.
Error if expiry date of server, intermediate, root certificate has passed, or start date is not yet reached.
Error if server, intermediate, root certificate is invalid, including missing SAN values, or signed by an untrusted certificate authority.
Error if HTTP response is not received within 15 seconds.
Error if HTTP response is slower than average by 200%.
Error if HTTP response code is not 200-299, or 30X redirect.
Error if HTTP response does not contain the expected response content (text).
Error if TCP check (connection) is not complete within 3 seconds. (Only executed when HTTP check fails).
Error if IP check (ping response) is not received within 2 seconds. (Only executed when TCP check fails).
Date and Time shown for the most recent failure 'Last Failure', when node is in the warning or failed state.
Date and Time shown for the initial failure 'First Failure', when consecutive failures have occurred. 'First Failure' is reset upon node returning to a healthy state (green state).
Date and Time shown for the most recent alert 'Last Alert', when node has returned to a healthy state (green state).
Automatic bubble up of warning and failure states (yellow and red states), when 2 consecutive alerts have occurred for a given child node.
Bubbled up alerts propagate to the root/top level node.
Ability to suppress bubbled up alerts - at the source of the alert - for 24 hours.

[General]
Browser based tree view UI, with in-built browser zoom options.
Single click to zoom to any individual node (useful when browser zoom is set to a low value in order to display many nodes).
Expand and collapse button for each parent node.
UI options for spacing between parent and child nodes, and horizontal or vertical display of child nodes.
Automatic polling of all HTTP targets at 1 minute intervals.
Automatic refresh of browser UI at 1 minute intervals.
HTTP check automatically follows 30X redirects and conducts checks against the target location.
Logging of all failures to the console UI, containing local and UTC time that each failure occurred.
Multi-threaded checks, ensuring slow response / failure of one node does not block the check of others.
Runs on local URL http://127.0.0.1:55480, with port configurable via "Urls" setting in appsettings.json.
All configurations persisted to a single portable JSON file 'handydash-configuration.json' located under the wwwroot folder.
Cross platform support, including Windows, Linux, and macOS (please enquire about further platforms).