Firefox – Fix Black Screen Playing Adobe Flash Videos

firefoxflashvideovideo player

After upgrading to Firefox 34, Flash videos stopped working. A black screen was presented, with no hint to the problem. Following these instructions and these other instructions, would prove futile.

Setting YouTube to playback using HTML5 also did not resolve the problem.

Best Answer

The Flashblock add-on is incompatible with Firefox 34; remove the add-on.

The following might work (untested):

Start Firefox and press Alt+h to open the Help menu
Press t to select Troubleshooting Information
Click the button for Open Containing Folder (or Open Directory)
Create a folder (directory) named Chrome
Create a new file named userContent.css

Copy the following text into the new file:

/* Flash Block */
@namespace url(http://www.w3.org/1999/xhtml);
@-moz-document domain("youtube.com"){
#theater-background { display:none !important;}
}

Save and close the file
Restart Firefox

Related Solutions

Ubuntu – Flash player (in Firefox) is unstable in 14.04

Here's a script that installs the latest version of pepper flash on firefox. It might fix your problem. https://db.tt/rHEJ2e0l

to run it, open terminal, cd into the location where the script is and install type:

chmod +x freshplayer_maintainer.sh; ./freshplayer_maintainer.sh

and the rest should be self explanatory

Here is the code from Tatakai Wasumi's answer above, in case their dropbox link goes kaput.

#!/bin/bash
# ----------------------------------
# Author: Jonathan Soivilus
# This script facilitates the installation and maintenance of freshplayer plugin on Debian based systems
# Fresh player wrapper is mainly developed by i-rinat https://github.com/i-rinat/freshplayerplugin 
# Version 1.1
# To run this scrip, open the terminal type: chmod +x freshplayer_maintainer.sh; ./freshplayer_maintainer.sh


function install_plugin(){
  echo "Getting dependencies..."
  HWFILE=/opt/google/chrome/PepperFlash/libpepflashplayer.so;

  if [ -f $HWFILE ];then
     sudo apt-get install build-essential git cmake pkg-config libglib2.0-dev libasound2-dev libx11-dev libgl1-mesa-dev libgles2-mesa-dev liburiparser-dev libcairo2-dev libpango1.0-dev libpangocairo-1.0-0 libpangoft2-1.0-0 libfreetype6-dev libgtk2.0-dev libxinerama-dev libconfig-dev libevent-dev;
  else 
     sudo add-apt-repository -y ppa:skunk/pepper-flash;
     sudo apt-get update;
     sudo apt-get install --no-install-recommends pepflashplugin-installer;
     sudo apt-get install build-essential git cmake pkg-config libglib2.0-dev libasound2-dev libx11-dev libgl1-mesa-dev libgles2-mesa-dev liburiparser-dev libcairo2-dev libpango1.0-dev libpangocairo-1.0-0 libpangoft2-1.0-0 libfreetype6-dev libgtk2.0-dev libxinerama-dev libconfig-dev libevent-dev ragel;    
     sudo mkdir -p /opt/google/chrome/PepperFlash; 
     sudo ln -s /usr/lib/pepflashplugin-installer/libpepflashplayer.so /opt/google/chrome/PepperFlash;
  fi

  cd;

  git clone https://github.com/i-rinat/freshplayerplugin.git;

  cd freshplayerplugin; mkdir build; cd build; cmake ..; make; 

  echo ""

  while true
  do
  read -p "Install plugin system wide? [Y/N] " yn

    case "$yn" in
            y|Y)  sudo ln -s ~/freshplayerplugin/build/libfreshwrapper.so /usr/lib/mozilla/plugins
        break;;
            n|N)  mkdir -p ~/.mozilla/plugins; ln -s ~/freshplayerplugin/build/libfreshwrapper.so ~/.mozilla/plugins
        break;;
             * ) echo  -e $RED "Invalid Choice";;
    esac
  done

  echo ""
  echo "Installation complete!"
  echo ""

}

function uninstall_plugin(){
  rm -rf ~/freshplayerplugin;
  HWFILE=~/.config/freshwrapper.conf;
  FRESHFILE=/usr/lib/mozilla/plugins/libfreshwrapper.so;
  FRESHFILE2=~/.mozilla/plugins/libfreshwrapper.so;
  sudo rm -f $HWFILE $FRESHFILE $FRESHFILE2;
}

function update_plugin(){
  cd ~/freshplayerplugin; git pull; cd build; cmake -DCMAKE_BUILD_TYPE=RelWithDebInfo ..; make;
}
function enable_disable_hW(){
  HWFILE=~/.config/freshwrapper.conf;

  if [ -f $HWFILE ];
  then
     rm  $HWFILE;
    printf "Hardware acceleration DISABLED \n\n"
  else 
    echo exp_enable_3d = 1 > $HWFILE;
    echo "flash_command_line = \"enable_hw_video_decode=1,enable_stagevideo_auto=1\"" >>$HWFILE
    printf "Hardware acceleration ENABLED \n\n"

  fi
}


function enable_disable(){
  FILELOC1=~/freshplayerplugin/build/libfreshwrapper.so;
  FILELOC2=/usr/lib/mozilla/plugins/libfreshwrapper.so;
  FILELOC3=~/.mozilla/plugins/libfreshwrapper.so;


   if [[ -f $FILELOC2 || -f $FILELOC3 ]]; then
    sudo rm -f $FILELOC2 $FILELOC3;
    printf "fresh player plugin DISABLED \n\n"

  else 
  while true
   do
     read -p "Enable system wide or not [Y/N]: " yn
    case "$yn" in
            y|Y)sudo ln -s $FILELOC1 /usr/lib/mozilla/plugins 
        break;;
            n|N)  ln -s $FILELOC1 ~/.mozilla/plugins
        break;;
             * ) echo  -e $RED "Invalid choice";;
      esac
    done
    printf "fresh player plugin ENABLED \n\n"

  fi
}

k=1

clear

printf "Welcome to fresh player plugin Maintainer v1.1 \n\n"

PS3='Choose an option: '

options=("Install freshplayer plugin" "enable or disable hardware acceleration" "enable or disable plugin" "update plugin" "uninstall plugin" "Quit")

select items in "${options[@]}"

do
  case $items in
    "Install freshplayer plugin")
      install_plugin;
    ;;
    "enable or disable hardware acceleration")
      enable_disable_hW
    ;;
    "enable or disable plugin")
      enable_disable
    ;;
    "update plugin")
      echo "Updating fresh player plugin..."
      update_plugin
      echo ""
    ;;
    "uninstall plugin")
     echo "uninstalling plugin..."
      uninstall_plugin
     echo ""
     echo "fresh player plugin has been successfully removed from your system"
     echo ""
     ;;
    "Quit")
      break
    ;;
    *) echo  -e $RED "invalid option";;
  esac

  for i in "${options[@]}"
  do
    echo $((k++))")$i"

  done
  k=1;

done
clear

Ubuntu – Flash no longer working in firefox

Try installing flash with this command:

sudo apt-get install flashplugin-installer

Best Answer

Related Solutions

Ubuntu – Flash player (in Firefox) is unstable in 14.04

Ubuntu – Flash no longer working in firefox

Related Question