In the previous versions, I used the keyboard [SHIFT-DELETE] key-combo to to delete highlighted posts as opposed to right-clicking and selecting from the menu. In 6.0b4, the ability to do this via the keyboard is gone, you can only do so with the right-click/menu method. The menu is long, it takes a moment to find the 'Delete' option, and not mistakingly select the 'Delete all Posts' item.
Hopefully this is only because it's beta, and the option will return