Script Runner Error 'Failed type checking and we don't know why.........'

[Sandra Meessen]

Hello, my script field (via scriptrunner functionality) gives me a warning, a bit a confusing warning, see screenprint:

  

In a few weeks we upgrade from Jira version v7.1.10 to v7.11 and Scriptrunner from 5.1.6.2 to 5.4.12 and I wonder if this warning is going to give me trouble then. Is it really "not my fault" and no disaster will happen? Can I get ride of this warning somehow?

I know this question is asked before (https://community.atlassian.com/t5/Jira-questions/Script-Runner-Error-Failed-type-checking/qaq-p/153957), but I don't see really an answer to my question/worry in the answers over there.

Thanks!