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How to resove: Firefox prevented this page from loading...

  • 10 replies
  • 1 has this problem
  • 1 view
  • Last reply by CiaoBella1

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Blocked by Content Security Policy

An error occurred during a connection to www.scribd.com.

"Firefox prevented this page from loading in this way because the page has a content security policy that disallows it." On IE, the message said it cannot be loaded in a FRAME. It's a letter!

I looked at and tried some instructions in Content Blocking. No solutions are there. Thank you.

Blocked by Content Security Policy An error occurred during a connection to www.scribd.com. "Firefox prevented this page from loading in this way because the page has a content security policy that disallows it." On IE, the message said it cannot be loaded in a FRAME. It's a letter! I looked at and tried some instructions in Content Blocking. No solutions are there. Thank you.

All Replies (10)

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This isn't about content blocking, but about CSP policy rules. The website tries to load a page in an iframe and that isn't allowed.

The only workaround is to open the frame URL in a new tab (right-click: This Frame -> Open Frame in New Tab).

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The option to right click to open isn't in Firefox, just IE. If so, it wouldn't bother me.

Thank you.

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Hi CiaoBella1, could you share a link to a page where you have this problem?

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Hi CiaoBella1, the framed page loads from:

https://www.scribd.com/embeds/415706656/content?start_page=1&view_mode=scroll&show_recommendations=false&access_key=key-toL6xFr7MUL7ayGHnS4i

and the page is sent with this header:

content-security-policy: frame-ancestors 'self'

"frame-ancestors" refers to what sites/pages are allowed to embed the content, and 'self' limits the embedding to https://www.scribd.com

That seems like a mistake, but it needs to be fixed by scribd. Until then, you can pop the frame that didn't load into a separate tab using:

right-click > This Frame > Open Frame in New Tab

Ref. https://developer.mozilla.org/docs/Web/HTTP/Headers/Content-Security-Policy/frame-ancestors

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I only understand that scribd has the issue.

Pop the frame? Don't understand, but I know that you cannot right click from FF.

I read the letter already. Can I assume it's a one-off issue (or low probability)?

Thank you for your effort and response. You shaved, didn't you?

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Hi CiaoBella1, yes, I shaved it.

I'm puzzled about this part:

I know that you cannot right click from FF.

You cannot right-click the "Blocked by Content Security Policy" text and get the context menu? Does it work any better if you hold down the Shift key while right-clicking?

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No website was underlined and I could not see that the website was scribd (if I remember correctly). So yes, I could not get any reaction to a potential right-click action. I think I learned from IE that it was scribd.com.

Just went to the website from the link I posted above. Apparently scribd.com fixed their error/s because the letter is now visible on the HR.

Thank you,

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Interesting - yes, I am sure the first screen box was what I saw (I've never worked w/it before) and ignored. The developer tools I don't know how to work with at all.

Ahh. Thank you.