In the selection interface, when running a tool such as wiggle or shake, selecting a segment in the Rama map causes all available tools to be hidden. The current tool continues running, although the clock/progress indicator in the upper left is no longer displayed, so it's not clear that the tool is still running. The normal keyboard shortcut won't terminate the running tool. For example, when this happens, typing "w" to end a wiggle won't work. The escape key (Windows shortcut) still terminates the running tool, however.
This problem does not occur in the original interface.
I've also experienced this. It seems to be cleared up by unchecking "Fade GUI" in the view menu.
I'm not able to reproduce the effect of "Fade GUI" on Windows. When selecting a segment in the Rama map with tool such as wiggle or shake running in the selection interface, the available tools at the bottom of the screen and progress indicator disappear. The tool is still running, and the normal keyboard shortcuts no longer end the tool. The escape key still ends the tool. On Windows, this happens regardless of the "Fade GUI" and "Hide GUI" settings.
Old feedback, but still an issue on 20180725-d14dae34c3-win_x86-devprev.
