add id tag to html page on Mendix 9?

How do I add an “id” tag to the very beginning of my html file?  I would like to use for my whole site a tag that has multiple variables in it.   This is how it looks like:   This is how I wanted to look:      
1 answers

I was able to figure it out. I deployed my project, copied the index.html from the deployment/web folders into them/web and added the tag manually. if you have a more elegant way of doing this, please let me know.