Python View: CEFNodeView Error

Python View nodes have stopped displaying an Output Preview within the configurator and raise this error:

 ERROR CEFNodeView Uncaught (in promise) SecurityError: Sandbox access violation: Blocked a frame at "http://org.knime.core.ui.dialog" from accessing a frame at "http://org.knime.core.ui.dialog".  The frame being accessed is sandboxed and lacks the "allow-same-origin" flag. (source: http://org.knime.core.ui.dialog/uiext-dialog/3_3/assets/index-6ef07e53.js; line: 879)

The Python Interactive View still works fine from the workspace, it just doesn’t load in the configurator. Does anyone know how to fix this?

Cheers!