The tutorial is not up-to-date, in the Github the second ExecStart has been transformed into a ExecStartPost: github.com/knro/indiwebmanager/blob/mast...diwebmanager.service The only issue I have right now is that the python package "requests" is a prerequisite but is sometimes not installed on some systems. I have posted a ticket on the GitHub page. I suggest to add the following to the installation instructions:
sudo apt-get install python-pip pip install --upgrade pip pip install requests