Thanks @siim I misunderstood the guide, now I will follow the guide from step 0 again, let's see how it goes.

As I said before plugin API is just prototype and now we are eager to extend it

My bad, sorry. Than you have to accept self signed SSL certificate. Copy paste from tutorial: Now open your browser browser at https://localhost:9999/plugin.js to accept self signed SSL certificate. Then open your browser at www.windy.com/dev to test your plugin. If it fails, make sure that your plugin is correctly built and accessible with your browser at https://localhost:9999/plugin.js.

@cap-reimann https://community.windy.com/topic/3952/how-to-set-up-a-windy-alert

@ac5a I have resolved, this issue. You have to click the slider to automatically reload on default. Please delete this thread, if no longer needed.