Your software
My Mautic version is: 4.4.5
My PHP version is: 7.4
My Database type and version is: Mysql
Your problem
My problem is:
When trying to register a pageview in our webapplication (with a created contact) through javascript. Nothing is added to the Contact’s record.
The most common problem: mautic will NOT track your request if you are logged in to mautic at the same time. So make sure to clear the browser or better use another browser.
You mentioned that it is a webapplication. Please note that the javascript code just fires once every page you requested. If your webapplication is a single web application and loads via ajax other views, mautic will not recognize that with the default code.