Reply To: Change max width of Tagline in site identity

The masthead is made up of 3 columns: 1. the logo & tagline – 2. the primary menu – 3. the search/account/cart section

This is the default CSS that determines the width of the 3 columns:

#masthead > .container {
    grid-template-columns: minmax(auto,300px) auto auto;
}

You could add Additional CSS such as this:

#masthead > .container {
    grid-template-columns: auto auto auto;
}

If you have a lot of menu items in the primary menu you may need to experiment with the widths to get it how you like.