TypeError: Cannot read property hasTrackId of null

While running locally after upgrading my project form Mendix 6.10.16 to 7.19.1, I am receiving this error after logging into the application and landing on the home page. After closing the default “An error occurred, please contact your system administrator.” error message the app seems to work fine – unless you refresh the browser, in which the error repeats.  Anybody encountered a similar issue? Cannot read property 'hasTrackId' of null TypeError: Cannot read property 'hasTrackId' of null at Object.e.onPersistViewState (http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:82:61199) at Object.<anonymous> (http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:82:30827) at w (http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:51:299728) at Generator._invoke (http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:51:299516) at Generator.e.(anonymous function) [as next] (http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:51:299907) at w (http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:51:299728) at t (http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:51:300043) at http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:51:300339 at new Promise (<anonymous>) at o (http://localhost:8080/mxclientsystem/mxui/mxui.js?636851349496725645:51:299990)  
1 answers

Poster found the answer, adding it here to mark the post as answered and future reference:

Thanks to everyone who responded. I found the issue. A show form action was being called twice, once on a subflow and then on the main flow. An over sight that was never an issue before. #facepalm