2019.2 has been a bumper release with loads of great new features: parameter actions, hide/show containers, vector maps, spatial calculations and lots more. This blog includes a links to a workbook with a number of example use cases.
The second beta of 2019.2 includes an upgrade to Parameter Actions, which now allow you to select multiple values and pass an aggregation of those values to a parameter. This blog explains this new feature and walks through an example.
The Tableau 2019.2 beta introduces Show/Hide Container functionality, which, combined with the new Parameter Actions as well as Set Actions, allows for popup customisable charts.