To install qt511-qtmacextras, run the following command in macOS terminal (Applications->Utilities->Terminal)
sudo port install qt511-qtmacextras
To see what files were installed by qt511-qtmacextras, run:
port contents qt511-qtmacextras
To later upgrade qt511-qtmacextras, run:
sudo port selfupdate && sudo port upgrade qt511-qtmacextras
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