When you try and load the Visual (HTML, XHTML, JSP, JSF) Page Designer on Linux, it’s possible it might fail to load with an error that looks like the following:
Unhandled event loop exception
XPCOM error
Thanks to user Pantein for sending in the solution. The error is caused by the system not having libstdc++5 installed or an older version of it being installed. A relatively new version of the library is required for the embedded Mozilla component to operate correctly inside of the Eclipse platform.