Deciding where to start my open-source developer path was maybe the hardest part of my contribution so far (I hope)
The next step is to set up environment and run the project locally.
Without any positive attitude or expectations I went to the link which gave me some instructions how to set all the required dependencies and start debugger.
git clone email@example.com:devtools-html/debugger.html.git
So far so good!
Next step was to install all the dependencies with even more magical command: yarn install. Nothing stressful and with no pain I have successfully started the project on port 8000 with yarn start.
And that was it!
Tip for the future: Have more courage and Murphy's law doesn't always work.