macOS Sierra Dock open app indicator missing My Dock's open app indicator is suddenly missing. There is no more black dot at the bottom of my open app indicator.

What I did (but failed):


I am turning on my open app indicator in the system preference.
I have tried to remove ~/Library/Preferences/com.apple.dock.plist


When I move the dock position to Left or Right though, the indicator appears. Only when at the bottom it doesn't appear. Anybody knows why?

I am on macOS Sierra 10.12.6. 

Adding picture.

This really doesn't show my point so well. When I took the screenshot, the open app indicator is there. But it doesn't show up in my real desktop.
I've seen that happen when a system isn't logged out for months, so the first thing I would do is save work and then log out.

When you log back in, consider holding the shift key (or not having all the apps re-start) as well if a quick log out and log in don't clean things.


On rare occasion the saved application state gets messed up and a cleaner log in can help.
On other rare occasions it’s genie effect and software bugs - Visual bug in Dock after macOS Mojave installation
Be sure it’s not just a display failure as well. I would rule that in or out with some tests below:


Start with logging out and then restarting with no accounts logged in. Should you have something you can reproduce right after a restart, would be when I would get a sysdiagnose of the dock process and get a support ticket in to Apple.

Lastly, since you were removing preference files from under the preference database engine, consider trying a new user account to be sure things are good. In that case, you can consider moving files and settings over to a new account or know that it's just a user library preference corruption issue.

If you reproduce this on a new account, a backup and reinstall of the OS would be my next step. Hopefully you don't need to do an erase install, so start with an in-place reinstall where your user data isn't erased.