Not that I know of. If the editor is ever updated, that is one of the features I'd like also, along with all the other game-play options, like reset shot, camera, etc.

Currently not, there was a workaround to get that working in earlier versions but that doesn't work since the editor was migrated from the offline menu to its own place in the main menu.

No idea if they're planning on integrating it whenever they come around to actually do something else to the editor then introducing new bugs but imho, while it would be nice, jumping while testing isn't in the top 5 of stuff that needs to be fixed or changed in the editor.