I have no validator in the properties panel of the transition.

[Deleted user]

How can I activate the validator property?

Jira Server Core 8.3.2. 

[Anton_Ermolaev · Accepted solution]

Properties are inactive as in the picture below? 

In this case, you probably have the project administrator permission but that's not enough. You should have Jira administrators permission

https://confluence.atlassian.com/adminjiracloud/advanced-workflow-configuration-776636620.html

[Deleted user]

I'm already in the group of the jira administrators, But I can't see the entry "Validators()".
Is there maybe a missing service or  plugin?

[Anton_Ermolaev]

please attach a screenshot where you expect to see "Validators()", but don't see it?

[Deleted user]

Here are two screenshots. (from the transition "ticket schließen") The red line marks the place where i expect the entry validators.

[Deleted user]

I think the term validator is corresponding to "Bestätigungen" in german. So in this case the issue is solved.

[Luke]

Can confirm, validators is translated to "Bestätigungen" if you've got it set to German.
Had to get used to it as well when switching from an English instance to a German one.