In the installation path of /var/lib/tomcat7/webapps/ROOT there is a file 'index.html' that is displayed by default by the server. This file has improper HTML start/end structure for the <p> element on line 28:
diff index.html_fixed index.html
24c24
< <p><b>tomcat7-admin</b>: This package installs two web applications that can help managing this Tomcat instance. Once installed, you can access the <a href="manager/html">manager webapp</a> and the <a href="host-manager/html">host-manager webapp</a>.</p>
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> <p><b>tomcat7-admin</b>: This package installs two web applications that can help managing this Tomcat instance. Once installed, you can access the <a href="manager/html">manager webapp</a> and the <a href="host-manager/html">host-manager webapp</a>.<p>
Thank you for the report, a fix has been applied in Debian for tomcat7 (>> 7.0.63-1) and tomcat8 (>> 8.0.24-1).