Hi,
It is an issue with WP Rocket cache. It looks very similar to a previous problem, and in that case the WP Rocket caused a problem by adding a custom functions scope to localized script fragments – and I am seeing the same code fragment on the page source here. They were notified about the problem, hopefully they will resolve it within the upcoming release.
I’m not exactly sure which of their modules is causing the problem – try turning off the asset/script caches or some of the options there. If that does not help, then probably the plugin has to be disabled.