Supersized making the website very slow

Hi there,

the website of our customer is getting slower and slower. Checking it witht Firebug, I have noticed that there are a number of queries which don’t make any sense. Like:
https://www.test-ergoneers.de/wp-content/themes/ergoneers_mobil/img/icons/strongTestdrive/strongulliFreelydefineyourD-Lab3cockpitandobserveallvaluesinrealtime/liliRecordallvaluessynchronously/liliSettriggersandwritenotes/liliSeelivedatawhiledriving/li/strongTestdrive/strongulliFreelydefineyourD-Lab3cockpitandobserveallvaluesinrealtime/liliRecordallvaluessynchronously/liliSettriggersandwritenotes/liliSeelivedatawhiledriving/li/ul

This awesome URL is a abstract text of one post ??
I could narrow it down to make it sure it is Plugin Supersized causing this trouble, but I have no idea how to solve this.

Could some one please help me?

Thank you!

The URL of the test-website: https://www.test-ergoneers.de/

Best regards
Marko

https://www.ads-software.com/plugins/wp-supersized/