JS seems to not be loading?

JS file initializing variables for second JS file, displaying webpage of computer use time. The first file doesn't seem to be loading.

I am planning on having a python program rename the current mainContent.js file to a timestamp, and add another mainContent, every time someone at a computer finishes their logged in session.

Here is a github of my files so far:
https://github.com/ealop123/fabio

Here is the actual webpage:
https://ealop123.github.io/fabio/

Here is the part of my code that I think there is a problem with
7: <script type="text/javascript" scr="mainContent.js"></script> 8: <script type="text/javascript" src="main.js"></script>
and here is the error JS is throwing:
Uncaught ReferenceError: _userName is not defined main.js:28

It is supposed to take the variables from the first file, then load them into the second file. I have been reading everything I can and for the life of me have no idea what's going wrong.