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When you open a page for editing and reload it in the browser, an extra semicolon is added to the URL fragment and the server returns a 404 error. Every subsequent reload adds another semicolon. This issue occurs with older versions of the Tomcat application server. To resolve this issue, upgrade to Tomcat 7.0.47+. See 

Tomcat 8 using BCEL may throw class format exception

Tomcat 7.0.66+ Trailing slash issue

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