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browser.pagethumbnails.capturing_disabled - should be set to false. Check https://developer.mozilla.org

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Most sites make a lot of noise about browser.pagethumbnails.capturing_disabled - and they repeat just one after another that this should be set to "true" to prevent thumbnail storage. But when you look at the right source, like: https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/Preference_reference/browser.pagethumbnails.capturing_disabled

true (default)

   The application creates screenshots of visited web pages.

false

   The application doesn't create screenshots of visited web pages. 

The name of the parameter is confusing. But it seems that it should be set to "false" to prevent thumbnail storage. And the right question should be about reading abilities ;) But I will ask another one - does Mozilla will try to conntact with those sites and say them that they are wrong? Have a nice day folks! :)

Most sites make a lot of noise about browser.pagethumbnails.capturing_disabled - and they repeat just one after another that this should be set to "true" to prevent thumbnail storage. But when you look at the right source, like: https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/Preference_reference/browser.pagethumbnails.capturing_disabled true (default) The application creates screenshots of visited web pages. false The application doesn't create screenshots of visited web pages. The name of the parameter is confusing. But it seems that it should be set to "false" to prevent thumbnail storage. And the right question should be about reading abilities ;) But I will ask another one - does Mozilla will try to conntact with those sites and say them that they are wrong? Have a nice day folks! :)

All Replies (4)

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Firefox has a mix of preferences saying "enabled" or "disabled" and of course true and false have the opposite effect depending on which you're changing. Since this one has "disabled" in the name, "true" definitely should disable the thumbnails and therefore the documentation would be incorrect on MDN.

When I look at the source code (browser-thumbnails.js lines 34-36), it seems that "true" would completely bypass the capturing of new thumbnails and the updating of old ones. Not sure it would clear the ones already saved.

Have you tested to confirm?

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You will have to delete the Thumbnails folder in the Firefox Profile Folder to remove already stored thumbnails.
The pref only prevent new thumbnails from getting generated.

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delete

Cartel modificouno o

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Hi Cartel, the last two posters in that thread said it worked for them. Which posts were you referring to?

Also, could you use a more family friendly avatar for this forum?