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Cannot install sling box plug in

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I had been using Firefox to open my Slingbox. Recently I was asked to install a plugin, but was blocked form doing it. I now cannot use my Slingbox with Firefox.

I had been using Firefox to open my Slingbox. Recently I was asked to install a plugin, but was blocked form doing it. I now cannot use my Slingbox with Firefox.

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This was probably disabled in the Firefox update because it is an unsigned addon. Firefox automatically disabled unsigned addons for user security.

To enable unsigned addons, please do the following:

  1. Go to about:config
  2. Click the I'll be careful button
  3. Locate the xpinstall.signatures.required boolean
  4. Toggle the value to false
  5. Go to the addon manager or about:addons
  6. Enable the desired addons

Please refer to these Mozilla articles for more information about unsigned addons and how to enabled them:

Warning: The steps above may present a security risk. Please use with caution and at your own risk.


Please consider advising the addon developer about the issue, so that they can get their addon signed as soon as possible.