Recently upgrade from mockk = "1.14.0" to mockk = "1.14.4" and got this exception: I'm rollback to previous version and works fine. Rolling back didn't resolve it for me - it was present in 1.13.x ...

In #3935, some issue led to a workaround requesting to drop all modifiers (before applying new ones). This workaround leads to issue with LexicalPreservingPrinter and sealed classes (JDK17). import ...