Odd bug I've noticed when Apex Launcher stays in memory for long periods of time. This bug was not present in versions prior to 0.5.
Icons on the dockbar will triple or quadruple. Attempting to drag them off will drag multiple copies of the same app icon onto the homescreen. All of these app shortcuts function, but as soon as any duplicate app shortcuts are pulled off of the dockbar, the launcher becomes unstable and has a high likelihood of force-closing.
Resetting the launcher immediately fixes the issue and causes the cloned shortcuts to disappear if they were placed on the homescreen.
This is also accompanied by a visual indicator--the app drawer shortcut becomes thicker and darker in appearance.
Relevant screenshot below:
nexus 4 - cyanogenmod 11 - .33/.98 hybrid radio - stock kernel
stuff and things.