• Start Windows in safe mode with networking enabled - https://support.microsoft.com/en-us/help/12376/windows-10-start-your-pc-in-safe-mode
• Still In Windows safe mode, start Thunderbird in Troubleshoot Mode - https://support.mozilla.org/en-US/kb/troubleshoot-mode-thunderbird

Does problem change? (many users have found antivirus software causing problems)

If it did not get better, try changing the hidden preference accessibility.force_disabled to 1.

Please post your results

I have Windows 11 - it is slow and sometimes it freezes and you get the message "Not Responding".

Takes long time to download messages form my Gmail account and the Tools / Messages / Filters do not work and loads them all in the Ibox folder, then I have to manually select Tools / Run Filters on Folders adn ask me to OK for each folder individually

The whole issue started about 2 1/2 weeks ago

Amparo

I have the same problem. TB is sometimes too slow. Typicaly - i click on other folder and then when I want to open e-mail, it take about 1-5 minutes. Then is all ok. But 1st message not.

I have Windows 11 - it is slow and sometimes it freezes and you get the message "Not Responding".

I refer you to my earlier posting https://support.mozilla.org/en-US/questions/1513098#answer-1735319

I have the same problem. TB is sometimes too slow. Typicaly - i click on other folder and then when I want to open e-mail, it take about 1-5 minutes. Then is all ok. But 1st message not.

I refer you to my earlier posting https://support.mozilla.org/en-US/questions/1513098#answer-1735319

Yučikala Amparo

Is 140 better for you?