Windows 10 reached EOS (end of support) on October 14, 2025. If you are on Windows 10, see this article.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More
This thread was archived. Please ask a new question if you need help.
Solved Archived

Thunderbird lag in MacOS Big Sur

Thunderbird Troubleshooting
Wayne Mery replied
huck2099
huck2099

Thunderbird ver. 78.4.3 (64-bit) Mac OS ver 11.0.1 Big Sur

Thunderbird become lag after upgrade the mac os to 11.0.1

Scroll the mouse, the "Subject Panel" moving very lag

Thunderbird ver. 78.4.3 (64-bit) Mac OS ver 11.0.1 Big Sur Thunderbird become lag after upgrade the mac os to 11.0.1 Scroll the mouse, the "Subject Panel" moving very lag

All Replies (6)

Wayne Mery
Wayne Mery
  • Top 25 Contributor
  • Moderator

Chosen Solution

see https://bugzilla.mozilla.org/show_bug.cgi?id=1677272

What language locale is Thunderbird? Do you have lots of fonts?

huck2099
huck2099 Question owner

I just have English fonts in Thunderbird.

I will try the Thunderbird beta version v84.0b2 (64-bit) later.

Thanks :)

huck2099
huck2099 Question owner

The lag issue is solved after update to 84.0b2.

Thanks for your help. :)

Wayne Mery
Wayne Mery
  • Top 25 Contributor
  • Moderator

We have something for you to try if you are able, to get your feedback. https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/cS4TP33hS7yHdUx2l1zlyQ/runs/0/artifacts/public/build/target.dmg which is 78.5.1 plus a patch. It will display as version 78.6.0 although some places might refer to it as "Thunderbird Daily" because it is a test build. Because you currently running beta, you will need to start Thunderbird from Mac terminal using --allow-downgrade

huck2099
huck2099 Question owner

I am install Thunderbird Daily and create a new user profile. After adding mail account and some newsgroup accounts, there is nothing show on the left panel. Its not working on my mac.

Thank you :)

Modified by huck2099

Wayne Mery
Wayne Mery
  • Top 25 Contributor
  • Moderator

If you are using version 78, Please do Help > About to get version 78.6.1, and tell us the results. Thanks.