When installing Tailwind it adds a main element like this <main class="container mx-auto mt-28 px-5 flex"> to application.html.erb. While this might be fine with a newly created apps, it's annoying for existing apps since it messes with your existing layout.
I'd either remove this completely or only add it if the <body> of application.html.erb looks like a default Rails app.
I'm happy to look into this.