MacOS Catalina Workaround

Apple have started requiring developer signatures in MacOS Catalina. This shows up as a warning box stating that plugin "can't be opened because its integrity cannot be verified."

The workaround for this problem is to remove the quarantine flag as follows:

  1. Install the plugin by following the instructions (effectively copying the MBR Color Corrector 3.plugin into /Library/Application Support/Adobe/Common/Plug-ins/7.0/MediaCore/).
  2. Open Terminal (for example, by opening Launch Pad and searching for Terminal)
  3. Enter the command
    sudo xattr -r -d "/Library/Application Support/Adobe/Common/Plug-ins/7.0/MediaCore/MBR Color Corrector 3.plugin"
    and press Enter

After doing so, you may have to hold the shift key while starting Premiere Pro for the first time. (Premiere Pro has a plugin cache that may remember that the plugin didn't work, but holding down shift Premiere Pro will rescan all the plugins and update the cache).