Here are some common reasons why users find that nothing is being blocked:

• They didn’t enter a list of sites to be blocked.
• They included URL protocol prefixes such as http:// or file:// in their list of sites (see Note under the text box!).
• They didn’t enter either a time period within which the sites should be blocked or a time limit after which the sites should be blocked.
• They selected within time periods AND after time limit but did not enter both a time period and a time limit. (See here for further explanation.)
• They didn’t select any days on which the sites should be blocked.
• They added keywords to the list of sites, but did not understand how keyword blocking works.

To add a block set:

Go to the General tab in Options, increase the number of block sets by one, and click the Save Options button at the bottom of the page. Use the Move Set buttons at the top of the new block set to move it to the desired place.

To remove a block set:

Use the Move Set buttons at the top of the block set to move it to the end of the block sets. Go to the General tab in Options, decrease the number of block sets by one, and click the Save Options button at the bottom of the page.

Alternatively, you can just click the Reset Options to Defaults button for the block set. The options will be reset and the block set will no longer be active. You don’t need to remove it.

If the override feature doesn’t seem to be having any effect, it’s most likely because you haven’t selected the option Allow temporary override for these sites for the relevant block sets.

In general, an Edge extension cannot prevent the user from uninstalling it, so LeechBlock cannot offer this as an option within the extension itself.

However, it is possible to “force install” an extension by setting a Microsoft Edge policy so that the extension cannot be removed or disabled. (You should create a backup of your LeechBlock settings before you attempt this solution: Options > General > Export.)

On Windows, the policy can be set via the Registry Editor:

• Navigate to the following registry key (or create it if it doesn’t exist):
  • HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Edge
• Add a new key under the Edge key (if it doesn’t already exist):
  • ExtensionInstallForcelist
• Add a new value to that key:
  • Name: 1 (or some higher number if 1 is already used)
  • Type: String (REG_SZ)
  • Data: hnncfhodpmpjchmmcnimoimkcojdmfhl

Warning: Do not attempt to edit the registry unless you really know what you’re doing! You should back up your registry before making any changes. The developer of LeechBlock will not be held responsible for any damage you do to your system by editing the registry.

In general, a Firefox extension cannot prevent the user from uninstalling it, so LeechBlock cannot offer this as an option within the extension itself.

However, it is possible to “lock” an extension by setting a Firefox policy so that the extension cannot be removed or disabled. (You should create a backup of your LeechBlock settings before you attempt this solution: Options > General > Export.)

On Windows, the policy can be set via the Registry Editor:

• Navigate to the following registry key:
  • HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Mozilla\Firefox
• Add a new key under the Firefox key (if it doesn’t already exist):
  • Extensions
• Add a new key under the Extensions key (if it doesn’t already exist):
  • Locked
• Add a new value to that key:
  • Name: 1 (or some higher number if 1 is already used)
  • Type: String (REG_SZ)
  • Data: leechblockng@proginosko.com

Warning: Do not attempt to edit the registry unless you really know what you’re doing! You should back up your registry before making any changes. The developer of LeechBlock will not be held responsible for any damage you do to your system by editing the registry.

For further information on setting Firefox policies on Windows, Mac, and Linux systems, see here.

Yes. The referrer prefix (>) can be used to block pages referred from a site.

For example, >somesite.com will block all pages where the referrer is somesite.com (i.e., if you follow a link from somesite.com then the linked page will be blocked).

Note that sometimes the URL of the referrer is not passed to the linked page, in which case LeechBlock will not detect it. In other words, do not expect this feature to work 100% of the time!

If you want referred pages to be allowed rather than blocked, you should select the option Treat referrers as allow-conditions rather than block-conditions under Advanced Options. Thus, if you were to select that option with the example above, the effect would be to allow all pages linked from somesite.com. (Note that this will have an effect only if you have also specified some sites to block when the referrer condition is not met.)

In general, a Chrome extension cannot prevent the user from uninstalling it, so LeechBlock cannot offer this as an option within the extension itself.

However, it is possible to “force install” an extension by setting a Chrome Enterprise policy so that the extension cannot be removed or disabled. (You should create a backup of your LeechBlock settings before you attempt this solution: Options > General > Export.)

On Windows, the policy can be set via the Registry Editor:

• Navigate to the following registry key:
  • HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Google\Chrome
• Add a new key under the Chrome key (if it doesn’t already exist):
  • ExtensionInstallForcelist
• Add a new value to that key:
  • Name: 1 (or some higher number if 1 is already used)
  • Type: String (REG_SZ)
  • Data: blaaajhemilngeeffpbfkdjjoefldkok;https://clients2.google.com/service/update2/crx

Warning: Do not attempt to edit the registry unless you really know what you’re doing! You should back up your registry before making any changes. The developer of LeechBlock will not be held responsible for any damage you do to your system by editing the registry.

For information on setting Chrome extension policies on Mac systems, see this article.

For information on setting Chrome extension policies on Linux systems, see this article.

You can use the userChrome browser customization file to remove the “Remove Extension” menu item from the Firefox toolbar. Carefully follow these steps:

• Locate your Firefox profile folder.
• Create a new folder chrome inside your profile folder (if it doesn’t already exist).
• Create a new file userChrome.css inside that folder with the following content: [label^='Remove Extension'] { display: none !important; }

You will need to close all Firefox windows and restart Firefox for it to take effect.

Note: If you’re using Firefox 69 or above, you’ll also need to go to about:config and ensure the toolkit.legacyUserProfileCustomizations.stylesheets preference is set to true (go here for more detailed instructions).

LeechBlock cannot disable private browsing, but there are other ways to do it.

LeechBlock does not collect, store, or transmit any personal information (other than the settings entered by the user, e.g., which sites to block).

LeechBlock may access the content of web pages (e.g., if the user has opted to block pages containing specific words or phrases) but it does not collect or store that content.

For an explanation of the browser permissions LeechBlock requires, go here.