Steps to reproduce:

1. Create a JSF project
2. Create a JSPX page with the following content:
   test.jspx

   <input type="submit" value="${hello}"/>${hello}
   

3. Open Page Design Options dialog->Substitutes EL-expressions
4. Create expression hello with value Hello World! and press OK
5. Click show bundle's messages as EL expressions button on the toolbar

Actual result:
${hello} expressions are substituted by Hello World!
Expected result:
${hello} expressions are not substituted and shown as is