When I search for an exact phrase on the English Wikipedia, while using Chrome browser (but not Firefox), I receive this error:
Internal error - [XZS4IgpAAEQAAAoljdUAAACR] 2019-10-02 14:45:54: Fatal exception of type "Wikimedia\Assert\PreconditionException"
For example, when I searched for "National Center for PTSD" I received the above message (URL of results page = https://en.wikipedia.org/w/index.php?cirrusUserTesting=glent_m0&search=%22National+Center+for+PTSD%22&title=Special:Search&go=Go )
I'm on a Win 10 desktop (64-bit; updated regularly; Malwarebytes; Kaspersky Total Security).
Chrome Version 77.0.3865.90 (Official Build) (64-bit).
Firefox 69.0.1 (64-bit)
My technical know-how is very limited. I apologize in advance if this is not the best way to report this anomaly. Thanks! - Mark