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Preview no longer works when I pass mouse over image in Persona add-ons

Before when I would hover my mouse over the images in the add-on themes (Personas for FireFox) it would change the image at the top of my browser so I could see what it would look like before I set it as background. Now, I get no preview at all and I have to actual set it as the background in order to see if I want it or not.... a very tedious and time consuming process. What happened? Why can't I see a preview anymore? Can I fix this? Thank you for your help!!!

Before when I would hover my mouse over the images in the add-on themes (Personas for FireFox) it would change the image at the top of my browser so I could see what it would look like before I set it as background. Now, I get no preview at all and I have to actual set it as the background in order to see if I want it or not.... a very tedious and time consuming process. What happened? Why can't I see a preview anymore? Can I fix this? Thank you for your help!!!

Chosen solution

Previewing a lightweight theme (Persona) only works on sites that are white-listed via an allow exception, so make sure to have an allow exception for the addons.mozilla.org domain. You can see the permissions for the domain in the current tab in:

  • Tools > Page Info > Permissions > [X] Install Add-ons

You can reset these prefs on the about:config page via the right-click context menu to the default value to restore the default software exceptions for installing add-ons from the Add-ons website. xpinstall.whitelist.add (addons.mozilla.org) xpinstall.whitelist.add.180 (marketplace.firefox.com)

If these prefs do not exist or are an empty string if you open the exception window then the corresponding default entry is recreated.

  • Tools > Options > Security : "Warn me when sites try to install add-ons": Exceptions
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Chosen Solution

Previewing a lightweight theme (Persona) only works on sites that are white-listed via an allow exception, so make sure to have an allow exception for the addons.mozilla.org domain. You can see the permissions for the domain in the current tab in:

  • Tools > Page Info > Permissions > [X] Install Add-ons

You can reset these prefs on the about:config page via the right-click context menu to the default value to restore the default software exceptions for installing add-ons from the Add-ons website. xpinstall.whitelist.add (addons.mozilla.org) xpinstall.whitelist.add.180 (marketplace.firefox.com)

If these prefs do not exist or are an empty string if you open the exception window then the corresponding default entry is recreated.

  • Tools > Options > Security : "Warn me when sites try to install add-ons": Exceptions

Thank you so much for helping me!