Thunderbird 157 Fixes a 100% CPU Bug and Adds Chat and FileLink Policies

Thunderbird 157 Fixes a 100% CPU Bug and Adds Chat and FileLink Policies

By Our editorial standards

Thunderbird 157 was released on September 30, two weeks after Thunderbird 156. It is mostly a fix release, and one fix in particular will be welcome on laptops.

The CPU bug

The status bar could stay active after activity had finished and keep a CPU core at 100%. On a desktop that means fan noise; on a laptop, a drained battery and a warm lap. If you noticed Thunderbird near the top of top or htop while idle, this is the fix.

Enterprise policies

Continuing the work-focused direction of recent releases:

  • DisableChat turns off the built-in chat
  • DisableFileLink turns off FileLink, the feature that uploads large attachments to a cloud service and sends a link instead

FileLink is the one administrators most often want off, since it sends attachments to third-party storage outside the organisation’s control.

Other changes

  • The Thundermail add-on moves to 2.0.16
  • The port field is optional in manual IMAP/POP configuration
  • Remote content can be viewed in OpenPGP messages with integrity protection

Fixes

  • IMAP: saving to the Sent folder, and messages disappearing
  • Authentication: Gmail OAuth2, Exchange NTLM, and SMTP
  • OpenPGP: valid keys being rejected
  • Calendar: CalDAV task syncing, invitations, and recurring event dates
  • Yahoo mail display issues

Getting it

Thunderbird updates itself when installed from Mozilla; Flathub and distribution packages follow. See our Thunderbird 156 download page for install options.

More news

Thunderbird 156 Adds Custom OAuth for POP3 and New Enterprise PoliciesThunderbird 156 extends custom OAuth support to POP3, adds enterprise policies, and fixes IMAP, POP3, attachment, OpenPGP, and calendar issues.Thunderbird 154 Adds an Optional System Tray Mode and Microsoft Graph SupportThunderbird's August release lets the client keep running in the tray after you close its last window, enables Microsoft Graph for Microsoft 365 mail accounts, and improves attachment handling and global search.Firefox 156 Brings a PDF Viewer Up to 45 Percent FasterFirefox 156 speeds up the built-in PDF viewer by as much as 45 percent and cuts resource use on large JPEGs, with Thunderbird 156 shipping alongside with custom OAuth for POP3.

Background reading

Explainers for the concepts behind this story.

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