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I am running Firefox 126.0-1 on an Arch Linux system. Most websites are failing to connect for security reasons.

Some sites, including google.com and nytimes.com, fail with an "SEC_ERROR_UNKNOWN_ISSUER" error, and their certificates confirm that they are respectively issued by Google Trust Services LLC and DigiCert Inc.

The website archlinux.org errors with "MOZILLA_PKIX_ERROR_MITM_DETECTED", stating that "Software is Preventing Firefox From Safely Connecting to This Site", citing in particular ISRG Root X1 as the problem. The certificate confirms that it is issued by Let's Encrypt.

The website duckduckgo.com simply errors with "SEC_ERROR_PATH_LEN_CONSTRAINT_INVALID" and states "Secure Connection Failed"

I have confirmed in preferences that my proxy settings are set to "No proxy" and the problem persists across troubleshooting mode and making a new profile. I have also tried removing the cert9.db file in a given profile folder.

I use a privoxy hosted on my home server to route Firefox traffic through a VPN. It usually works fine, but I am trying to set a few services to bypass the proxy using the "No proxy for" box in the Firefox connection settings - specifically streaming sites like netflix, hulu, and plex. Despite putting these domains in the "no proxy for" box, the proxy still seems to be applied - ie. Netflix fails to stream as it would if I were connecting through the VPN.

To test, I also tried adding "whatismyipaddress.com" to the "no proxy for" box, and this did successfully bypass the vpn (showing my real IP), so it is working to some degree. I can also confirm that that site shows my vpn IP when it is not on the whitelist.

I assume that these streaming services are connecting to a different domain when streaming video, which is not on the whitelist to bypass the proxy because I have not added them. Does anyone know if this is the case, and if so, how I could fix the issue?

Thanks.

I have been watching YouTube for years, issue free. This week I was blocked, as my computer may be blocking ads and thus violating You Tubes policy. How can I find and disable ad block programs/ extensions, thus allowing me to get back on You tube. I can recognize an outright program, but do not knew if extensions are in play that are not obvious to me. THANKS

I've appreciated using Thunderbird for an ad-free Hotmail experience for quite some time. I've changed my Hotmail password every few weeks lately and Thunderbird worked fine when I entered the new password at the prompt when Thunderbird started.

Just now however, I needed to get into my Microsoft account that uses the same password as my Hotmail account. My login to Microsoft failed. Trying to understand why, I looked in Thunderbird at the saved password for Hotmail's server:

oauth://login.microsoftonline.com (https://outlook.office.com/IMAP.AccessAsUser.All

https://outlook.office.com/POP.AccessAsUser.All 
https://outlook.office.com/SMTP.Send offline_access)

The saved password was a 464 character long ASCII string totally irrelevant to the password I'd selected for Hotmail and Microsoft.

I went through the password change process for Hotmail, was then able to get into my Microsoft account and restarted Thunderbird. As usual, Thunderbird asked for the new password. I entered it and was then able to receive new mail from the Hotmail server in Thunderbird. However, again, the saved password in Thunderbird for Hotmail was not the password I'd entered.

Next, I deleted the saved passwords in Thunderbird, restarted it and this time it prompted me to be sure I'd downloaded it from a reliable source. I've never seen that prompt before. It came with my Linux Mint installation, so I thought it would be safe, but again there's an irrelevant password saved for my Hotmail account.

It's like it eventually changes my password for Hotmail and Microsoft since I can get mail through Thunderbird with the odd password it saves, but if I use what should be my password for Hotmail or my Microsoft account via a web page interface, the password doesn't work.

I'll have to stop using Thunderbird if this continues.

bsky.app cookie continues to be loaded on computer even after I continually delete it, privacy set to strict and blocked under "managed exceptions, why is it being reloaded when I don't access the site. None of the sites I access are linked to it, only visited once and if this alternative to x continues to set cookies, how can I permanently block it, thought the exceptions list was supposed to keep blocking it. So far it's come back three times, I'll screenshot it next time and attach.

I have tried the suggestions as described in the following article: https://support.mozilla.org/bm/questions/1273784 However, am still having the issue. It's as if the settings are totally ignored. I am using version 108.0a1 of Firefox developer edition. Ideally what am trying to achieve is away to disable all features of ETP. I figured setting it to custom with all values unchecked would have done the trick but it's not working. What works is if I add the site to the list of Exceptions for Enhanced Tracking Protection, then I will see all Ads loaded just fine on the page. However, this is not viable for me as I have a large list of sites that I visit, and I need to see the ads on them.

Does anyone know of a way to get around this feature in FF?

Is there another setting am missing from the previous article?

I look at porn on my Android phone. I use Private Browsing to do so. Why are my Private Browsing addresses appearing as Firefox Suggest results that appear outside of Private Browsing as well? And why does Pornhub show me a personalized home page when I'm using Private Browsing? None of these pages are in my browser history because I've only accessed them via Private Browsing. But these "features" sort of defeat the purpose of it don't you think?

I've just switched from Chrome to Firefox and never had this issue with Chrome.

Hello all,

I had been using firefox as the standard browser for years, but since the DNS-over-HTTPS feature I have had trouble with protecting my family on the web via DNS filtering. Currently the only solution that has worked is to use a different browser (the Spin browser, for whoever is interested). I have Firefox blocked using the Android family link feature (and they can't install new apps without permission). Personally, I would love to move everyone back to Firefox, but I can't find a way to do it safely. Is there a way to effectively disable DNS-over-HTTPS such that it can't be changed (kids are pretty quick at figuring out that they can just go to the settings and figuring out that they can turn the feautre back on). A parental control feature would be ideal, so I can just set the DNS-over-HTTPS to use the family DNS filter in a way they can't turn it off. Does anyone have an helpful solution, or is Firefox dead for family protection?

Respectfully, Andrew

Bing says my browser is the one to set my SafeSearch on strict by default, but I can't find the option to turn it off. Is there even an option or is this a Bing issue?

Is there a security setting that allows me to show all my passwords rather than having to toggle them on each time?

I am a recluse. There's never anyone looking over my shoulder. I just don't want to have to mess with it anymore.

If there isn't, could some kind developer please make an add-on?

I am using two computers: an iMac (late 2009) running 10.13.6 (High Sierra) and a Macbook Pro (13-inch, 2012) running 10.15.7 (Catalina).

Thank you!

K

I am on endeavourOS (linux). Whenever I try to upload images for a profile picture to sites like youtube or X, the image becomes corrupted and doesn't upload correctly. It did this with whatsapp too and I had to use a separate app for it. Other posts said that disabling "privacy.resistFingerprinting" would fix it, but it's already disabled.

Attached below are an example of this bug and the contents of this image when viewed on a text editor.

I have just completely reinstalled Thunderbird v115.11.1 after uninstalling the previous installation. There are two problems, possibly linked to a faulty or missing setting.

Remote images will not display, even after specifically enabling remote images for each email, or after turning on "display remote content" as a default. Also it claims there is a potential security threat with Thunderbird's own web addresses: "live.thunderbird.net." and "addons.thunderbird.net.".

I have attached screen-shots of the error messages, and of a thunderbird email that fails to display its images.

I'm using 107.0.1 vers. At this link it states: https://support.mozilla.org/en-US/kb/view-pdf-files-firefox-or-choose-another-viewer#w_use-a-different-pdf-viewer-for-downloaded-pdf-files

Disable the built-in PDF viewer and use another viewer

You can also set a different third-party PDF viewer to handle PDF files, instead of Firefox’s built-in PDF viewer. To switch from using the built-in PDF viewer to another viewer: 1. Click the menu button and select . 2. In the panel, go down to the Applications section. (SO WHERE IN THE HELL IS THIS SECTION???) YOU CAN'T DO I never selected Mozilla to open any pdf and there's no where to opt out or change based on what all the troubleshooting tips say... All these tips must be located on a much older version of Firefox cause they ain't in my version OR they are hid under some dubious section... Pretty frustrating....when you want to use Adobe and can't cause I'm locked in under Firefox....don't know how that has happened unless it was done automatically under one of the many current upgrades that have been coming down over the last month.

I want to create a list of allowed web sites in settings/cookies&data/manage exceptions, but it seems I have to enter each site MANUALLY. I would like to do this more quickly and easily by just selecting sites in the "manage cookies" list and designating them as exceptions. Or is there already some other way to do this that I haven't found? Also, after I have made exceptions for all my important sites, by whatever means, can I assume that I can press "delete all" in the "manage cookies" list and the allowed sites will not have cookies removed? What happens to exceptions if I select "delete cookies and site data when Firefox is closed?" If there is no way to make exceptions other than manually, I respectively request that some convenient method be added to the program. Thanks for any response.

Hi, Before Firefox's Version 125.0.1 (64-bit) latest update I could download any file from my safe office environment, behind firewalls, VPN, ... Now despite of unchecking the "Block dangerous downloads" I'm still unable to download files. I have Windows 10 on my laptop.

Here are the steps: Click on a file, Save "File not downloaded. Potential security risk." Click on the message - Allow download The result is a file with content "HTTP Status 405 – Method Not Allowed".

Please help me to work the downloading again. I am aware of the safety but I want to switch off this feature.

Thanks in advance for help, Tibor

Since the update I've had a few issues, most I was able to fix but this one eludes me. Opening up various news sites I get the "Firefox prevented this page from reloading" error at the top and clicking allow does nothing. Anyone know how to get around this error? I'm not looking to totally disable the FF feature that prevents other pages from loading a different one, but just to browse the website after hitting 'allow'.

Thanks in advance.

For first time received email from breach-alerts@mozilla.com. Title is: Your monthly Mozilla Monitor report. Is this a scam? Other people have asked this question and Mozilla Firefox company has not made any attempt to answer these serious questions. If I do not hear back from Mozilla Firefox within a week I might remove Mozilla Firefox and use another company.

I am getting "Secure Connection Failed", Ive seen literally hundereds of same error also exist here. Like most of default solution (which is below) did not work for me. My laptops time is correct, And I highly doubt reddit and most of internet has issue with its security certificates. And other browser works just fine. So What is my solution other than immigrating to new browser?

https://support.mozilla.org/en-US/kb/secure-connection-failed-firefox-did-not-connect?as=u&utm_source=inproduct