Hi sfakianaris

You can try to set the Shockwave Flash plugin to "Never Activate" via "about:addons -> Plugins".

If you use a bookmark to access a specific page then instead navigate to this page starting with the main page or with the sign in page in case there is a problem with this bookmark.

Thank you cor-el for your reply. It helped me to see my playlists on the left side and it doesn't show me to sign in now. But on the top corner on the right of the screen, when I click on my picture as I am signed in, it still doesn't show me "switch accounts".

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

• make sure your extensions and filters are updated to the latest version
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

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. You can click shield icon for more detail and possibly disable the protection. You can check the Web Console for messages about blocked content.

• https://support.mozilla.org/en-US/kb/enhanced-tracking-protection-firefox-desktop
• https://support.mozilla.org/en-US/kb/trackers-and-scripts-firefox-blocks-enhanced-track

You can remove all data stored in Firefox for a specific domain via "Forget About This Site" in the right-click context menu of an history entry ("History -> Show All History" or "View -> Sidebar -> History").

Using "Forget About This Site" will remove all data stored in Firefox for this domain like history and cookies and passwords and exceptions and cache, so be cautious. If you have a password or other data for that domain that you do not want to lose then make sure to backup this data or make a note.

You can't recover from this 'forget' unless you have a backup of involved files.

If you revisit a 'forgotten' website then data for that website will be saved once again.

• https://support.mozilla.org/en-US/kb/delete-browsing-search-download-history-firefox

Thank you very much for your reply! It solved my problem!

Hello again, the same problem again. I don't see the "Switch accounts" up on the right corner when I click on my picture. It disappeared again... Before, when I had fixed it, it happened after I used "Forget About This Site". Now I did this again while I also turned off all add-ons and before that I deleted the Cache and Cookies. But the problem remains. I don't know what to do.

I have the same problem. It only happens when using Firefox, even after clearing cache and cookies and disabling all add-ons (or in Safe Mode).

I have the same problem. It only happens when using Firefox, even after clearing cache and cookies and disabling all add-ons (or in Safe Mode).

Hi. I can't agree with you more, it's very sad -( I have a successful login on the right side, and a login button on the left side.

I don't understand, it was solved again and after 1-2 days it happened again. I will follow all the instructions again and I hope that it will solve it. I was thinking, could it be because of an add-on? I will disable them and see...

I have simillar issue as person above, when i try to sub someone on youtube, it says your session has expired, and when i press log on page refreshes and literally same story, some on live streams works fine other just work for 1/4sec and do endless buffering, i have cleared appdata, cookies, cache, sync-off, and such, even fresh install after deleting appdata and no successful results.

Is there anyone at this forum that may know the fix for this issue?

I don't understand what's wrong. At the start Youtube and everything is ok (first picture) and through several minutes again same problem (second picture) :-( And between thees picture are just 2-3 minutes.

I have used Ccleaner to clear out cache and cookies, it worked for 1 day and back to same problem, Looks like firefox guys aint willing to help or have no fix for this issue

her browser updeit problem, need fix moderator

yana k said

I have the same problem. It only happens when using Firefox, even after clearing cache and cookies and disabling all add-ons (or in Safe Mode).

Hi. I can't agree with you more, it's very sad -( I have a successful login on the right side, and a login button on the left side.

I have this problem too! Chrome and Eage is working fine but only Firefox 80/80.0.1

I am find another solution from reddit https://www.reddit.com/r/firefox/comments/imp92h/how_to_fix_error_405_and_your_session_has_expired/g44ploa/

if you install KIS 2021 (KIS 21.1.15.500) please turn off "Inject scripts into web traffic to interact with web pages" in network settings

then everything working!

Youtube now opens my profile page , but the circle just spins and spins. Can't get video to add to list. I deactivated my Kapersky and it worked. Everything else I tried did not work.

My problem persists and I also use Kaspersky. Did you deactivate the extension of firefox? I deactivated it but, still the same problem. What is going on? Could it be because of the antivirus program? I am very satisfied with Mozilla firefox, but if the problem won't be solved, I'll stop using it. I can't save any playlist and I can't switch my accounts.

Here is what I sent Kapersky; Web-anti virus and Anti-banner turned off to work, But I had to turn anti-virus off and on after turning these two off.

Kaspersky replied back that they found a bug and correction will be in November update.

Same here. I disabled Kaspersky protection, but the problem persisted. Even removing the extension did not help. Youtube works fine without the problem on MS edge. No problem in my other pc with windows 10

Boot the computer in Windows Safe mode with network support to see if that has effect in case security software is causing problems.

• https://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/
• https://www.7tutorials.com/4-ways-boot-safe-mode-windows-10