I-Firefox Community Forum

Hello,

I have a problem with YouTube videos not playing on any website when using Mozilla Firefox. Whenever a site (like zamunda.net or other forums) embeds a YouTube video, I get the following message:

“Error 153 – video player configuration error” or sometimes “For your protection, this page will not allow Firefox to display the embedded content. To view this page, you must open it in a new window.”

If I open the same video directly on YouTube (youtube.com), it plays fine. This issue happens on all websites that have embedded YouTube videos, not just one.

Windows 11 25H2

Firefox Last Version

Could this be related to codec support (H.264 / MSE) or a security restriction with embedded frames? Any suggestions on how to fix or debug this would be appreciated.

Thank you, Panche

i HAVE SET FIREFOX AS MY DEFAULT BROWSER, BUT WHEN I TRY TO OPEN IT MICROSOFT BING POPS UP. THIS INFURIATES ME AND I WANT TO KNOW HOW TO STOP IT. IN THE CONTROL PANEL IT WILL ALSO NOT ALLOW ME TO REMOVE MICROSOFT EDGE.

I believe this is the correct topic for the issue I'm experiencing.

Since the last Firefox update, I'm now receiving feedback that Cloudflare is blocking webpages from being allowed to open. I use a secure external site for an application that is used.

Yes, I've restarted the server - this is where this issue resides. I have also, uninstalled and reinstalled Firefox. There has been no hardware changes made to this server. The switches and routers are all working, I restarted each of these in the correct order. So I've ruled out my infrastructure as the cause. I've verified all of the Mozilla/Firefox services are started and running. Interesting fact, go back to old school and I can ping the website/page where the Cloudflare issue is appearing. This tells me the site is available outside of Firefox.

Yes, I know I've broken Security within Firefox, just trying to figure out how to get around this issue and still use Firefox. I will turn things back on once I have this issue resolved.

I've added the parent site to the Enhanced Tracking Protection. It only allows me to add the parent site and not any sub webpage, site.com/support not allowed. That did not resolve the issue.

I turned off the DNS over HTTPS. This also did not resolve the issue.

If I am not receiving the Cloudflare webpage, other generic browser pages will return Server Not Found.

I'm not able to log into various accounts, including a special email account.

To even access this form, I've had to go to an unsupported OS, as there were issues even having this form to even load. I will need to go to various workstations to see if they are having the same issue... My thinking is fix the server, I know the issue is here and hopefully the workstations will automatically be resolved.

Some websites are loaded but only showing the XML, that is fine as I can read this. End User, this would be an issue for them.

I prefer to use Firefox over other browsers but I feel my hands are now tied with not being able to access items I use to be able to access. I have had to switch to a much less favored browser to try and work around this issue.

I know this issue has all occurred since the last update was automatically installed, something perhaps I should disable.

Any thoughts or work around?

I can't get into my Yahoo Email account, and keep getting, 'try again' which I've done repeatedly, then 'check internet connection' which seems to be fine, then to 'make sure Fox Fire has permission to enter', which until today I've thought they have always had because I've never had this problem before, so what could problem be today, and how do I fix it?

Hi, my location is Venezuela, and seems that I'm being blocked somewhere... I just want to confirm whether this is something on Mozilla's end (considering that their headquarters are in the US), or something on my government's end (since the ISP often blocks websites on orders from the state).

I can't sync my account or log in because of this, and generally, wherever the block comes from, they rarely give any warning. The main page loads normally; it's only the subdomains that are blocked, as far as I can see. For the record, this happens in Firefox for Desktop, and for Android too, wherever I'm on my home, using mobile data or using my office WiFi. This is not a browser error, in the capture u can see that the domains are solved correctly (even using the ISP's DNS), but u can't ping on the IP unless u turn on the VPN.

All Google services work fine for me, and I can't use a VPN all the time, so I'll have to switch to some chromium browser if this goes on too long (even if I don't want to).

Hi Folks - Per attached image, in the last few weeks (Dec.2025+ mainly), I get blocked from accessing web.Whatsapp.com on my Lenovo.X1 (Windows) laptop. It may work eventually but the block stays a long time etc.

Any ideas why & a fix much appreciated :)

Thx,

POB

After updating to latest version of Firefox, my request to go to website is showing "Access Denied" (e.g. www.aa.com)

Hello all! In this Firefox on Windows 11 setup I only have a few add-ons installed: Bitwarden ClearURLs Cookie AutoDelete DecentralEyes I don't care about Cookies PrivacyBadger uBlockOrigin

I sometimes have an issue: when I try to pay for a product or service, I end up in an error page and the only way to continue is by using another browser. I think that the problem is that my browser blocks pop-up windows. Which of the extensions does that? How can I get myself out of the need to use other browsers?

Thank in advance!

Error code 403

Error ID IjcpdgAAAAAAAAAAMfV4Nb~F

My IP is 49.245.120.53

I was trying to reach this page (a government service page), https://eservices.ica.gov.sg/ipapples/index.xhtml ,

I got this response: "Although the request was valid, the page/resource you are trying to reach is absolutely forbidden for some reason."

then I got this: "The web server thinks that the HTTP data stream sent by the web browser was correct, but access to the resource identified by the URL is forbidden for some reason. This is highly likely due to the reason that your recent action or browser behavior has been flagged as suspicious, either you have failed all authentication tests, including CAPTCHA, or performed an action on a protected application deemed illegal or malicious by the Web Application Firewall (WAF). Access to the requested page/resource is therefore blocked. If the source IP is on the blacklist, you will keep seeing this page until being removed from the blacklist. "

then it advised: "Clear your browser’s cache and try again. If you believe this to be erroneous, please contact the site owner citing the Event ID indicated above and provide a description of what you were doing before you were denied access."

Now, acting upon that advice, I've cleared my Firefox browser cache, but problem remains.

So, may I request that Mozilla remove (or a kind person help me to remove) my IP from blacklist? Thank you.

I am unable to open links to various sites, like OnShape, Banqiue of Montreal, Banque Laurentien and more... Any security that bvlocking access??? I am running Fox from Linux over Window 10. Says You have not granted any special permission to this site.../.

Help - any hint?

Martin

Hello. I did not receive an answer to my last help request. A Block Ad does not allow me to access this site: https://www.tempo.pt/lisboa.htm?utm_source=newsletter&utm_medium=email#-0eebc5457c97ef8bca0b518ed4194951 I need some help, please. Thank you.

duplicate of /questions/1555123 thread

Every time I do a search it takes me to a virus warning anad won't go further.