Overview
There are many checks in place to prevent you from putting code into a widget that will break the page, but sometimes it happens.
If you find that you can no longer access the site builder system, add '
/repair=true' to the page url.
Adding
/repair=true to the page url will make the contents of the individual widgets not be rendered.
The result is you will have the widget titles only along with the buttons to go in to edit and adjust the widget causing the problem.