Missing Invert button in Slide effect
The Invert button is missing in the effect 'Slide'. It is still present in version 18. As a result, this effect currently only works correctly for transitions in the timeline from top to bottom.
For new projects in V19 this is not such a big problem, because you can make the transition fit. But if you edit a finished project from V18 to V19, you won't notice the problem until the movie is rendered. In the attached picture you can see a repaired timeline from a v18 project. The transition was originally from bottom to top.