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How to block extension using policies.json

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  • Last reply by Jonathan

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Hi, I planned to block my users from installing extensions/add-ons. I found an article that might be the answer (https://support.mozilla.org/en-US/questions/1308646). I tried to create a simple policy (below), but somehow it does not work (I can still install any add-on/extension). What is wrong with my script? I'm using Firefox ESR 78.11.0 (64-bit) by the way.

My "policies.json" looks like this:

{

"policies": {
  "ExtensionSettings": {
    "*": {
      "blocked_install_message": "Blocked!",
      "install_sources": ["https://addons.mozilla.org/"],
      "installation_mode": "blocked"
    }
  }
}

Sincerely, Jonathan

Hi, I planned to block my users from installing extensions/add-ons. I found an article that might be the answer (https://support.mozilla.org/en-US/questions/1308646). I tried to create a simple policy (below), but somehow it does not work (I can still install any add-on/extension). What is wrong with my script? I'm using Firefox ESR 78.11.0 (64-bit) by the way. My "policies.json" looks like this: { "policies": { "ExtensionSettings": { "*": { "blocked_install_message": "Blocked!", "install_sources": ["https://addons.mozilla.org/"], "installation_mode": "blocked" } } } Sincerely, Jonathan

Chosen solution

See:

Note that your curly brackets do not match as you need to add one more '}'. You should see an error on about:policies#errors.

{
 "policies": {
  "ExtensionSettings": {
    "*": {
      "blocked_install_message": "Blocked!",
      "install_sources": ["https://addons.mozilla.org/"],
      "installation_mode": "blocked"
    }
  }.
 }
}

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All Replies (3)

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Chosen Solution

See:

Note that your curly brackets do not match as you need to add one more '}'. You should see an error on about:policies#errors.

{
 "policies": {
  "ExtensionSettings": {
    "*": {
      "blocked_install_message": "Blocked!",
      "install_sources": ["https://addons.mozilla.org/"],
      "installation_mode": "blocked"
    }
  }.
 }
}

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Cor-El, thank you --- just realized that I missed 1 "}".

Sincerely, Jonathan.