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Fedora 23/24 - HOWTO: flash 23 in Firefox

  1. Remove Your old flash plugin (if You have it)
    dnf remove flash-plugin

  2. Add rpmfusion repo
    http://rpmfusion.org/Configuration

  3. Install converter
    dnf update
    dnf install freshplayerplugin

  4. Go to: https://get.adobe.com/flashplayer/otherversions/ and chose FP 23.0 for...

  5. Download and unzip libpepflashplayer.so to /opt/google/chrome/PepperFlash (You may need to add folders and set permissions).

  6. Now You can check it here:
    https://www.adobe.com/software/flash/about/