dock
Sometimes when opening apps I get duplicate icons in the Dock for that app. This isn't really a problem, however I'm curious why macOS does this (I suppose this is more of a technical question).
This happens a lot especially with VS Code where I often launch the app with the code utility in the Terminal.
Why does macOS think these are different apps when they're the same binary?
This looks like it might be a problem with a system font. Try this...
/Applications)If any fonts are corrupt, this method should alert you to the problem.
I don't know how to dim inactive icons in the Dock. However, some people prefer the old-style two-dimensional dock that you can activate. It's certainly easier to discern which apps are open on this view.
To activate the 2D dock, open Terminal. Then type in the following command:
defaults write com.apple.dock no-glass -boolean YES
From there, you can log off & back on, and your Dock will have changed. If you ever need to revert this setting back run the above command again, but change the word YES for NO.
Best Answer
I don't have a specific answer as to what causes macOS to do this, however there is an issue on the VS Code GitHub repository which has lots of discussions about this (for VS Code app at least).
It seems to have something to do with launching an app directly (executing the binary inside XYZ.app/Contents/MacOS) instead of via Launch Services (the
opencommand).