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Cloudflare hosted site complains about Firefox but works with Chrome

  • 2 tontu
  • 2 am na jafe-jafe bii
  • 1 view
  • i mujjee tontu mooy em2jacks

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This site, Costco Instacart, worked perfectly with Firefox as recently as April 15, 2023 but today fails (see attached image): https://sameday.costco.com/store/costco/storefront?zipcode=11021

Cloudflare believes it is protecting itself from online attacks when accessed by Firefox. The same site worked perfectly today, on the same computer, using Google Chrome.

Cloudflare is a major CDN and many important commercial sites, like Costco Instacart, have their content delivered by Cloudflare so this is a major issue with Firefox. For the moment there is a work-around, use Chrome instead, but it would be better to have Firefox address issues with Cloudflare.

This site, Costco Instacart, worked perfectly with Firefox as recently as April 15, 2023 but today fails (see attached image): https://sameday.costco.com/store/costco/storefront?zipcode=11021 Cloudflare believes it is protecting itself from online attacks when accessed by Firefox. The same site worked perfectly today, on the same computer, using Google Chrome. Cloudflare is a major CDN and many important commercial sites, like Costco Instacart, have their content delivered by Cloudflare so this is a major issue with Firefox. For the moment there is a work-around, use Chrome instead, but it would be better to have Firefox address issues with Cloudflare.
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Saafara biñ tànn

Thanks for your reply.

The only extensions I have are AdBlock and Widevine.

I got the same problem with AdBlock disabled (it was already allowing all content from costco.com).

I also got the same problem after I restarted in troubleshoot mode. But, after I shut that down and restarted firefox normally, sameday.costco.com worked!

thanks again! --jack

Jàng tontu lii ci fi mu bokk 👍 0

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No problem here, I get redirected to the main page to provide an email address.

If you use extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) that can block content (Adblock Plus, NoScript, DuckDuckGo PE, Disconnect, Ghostery, Privacy Badger, uBlock Origin) always make sure such extensions do not block content.

Firefox shows a purple shield instead of a gray shield at the left end of the location/address bar in case Enhanced Tracking Protection is blocking content.

  • click the shield icon for more detail and possibly disable the protection

You can check the Web Console for relevant-looking messages about blocked content.

You can try these steps in case of issues with webpages:

You can reload webpage(s) and bypass the cache to refresh possibly outdated or corrupted files.

  • hold down the Shift key and left-click the Reload button
  • press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
  • press "Command + Shift + R" (Mac)

Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Settings).

"Remove the Cookies" for websites that cause problems:

  • Settings -> Privacy & Security
    Cookies and Site Data: "Manage Data"

"Clear the Cache":

  • Settings -> Privacy & Security
    Cookies and Site Data -> Clear Data -> [X] Cached Web Content -> Clear

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or if userChrome.css/userContent.css is causing the problem.

  • switch to the Default System theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window
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Saafara yiñ Tànn

Thanks for your reply.

The only extensions I have are AdBlock and Widevine.

I got the same problem with AdBlock disabled (it was already allowing all content from costco.com).

I also got the same problem after I restarted in troubleshoot mode. But, after I shut that down and restarted firefox normally, sameday.costco.com worked!

thanks again! --jack