This article describes ways the following error messages can be resolved.
As the first message says, it is often caused by a JS Optimizer Plugin.
If you have one of WP Rocket, AutoOptimize, Swift Performance or a similar plugin enabled please follow the following steps.
If this still doesn't solve the problem please contact our support.
WP Rocket
Deactivate "Combine JavaScript files"
AutoOptimize
Deactivate "Aggregate JS-files"
Swift Performance
Deactivate Merge Scripts