Mozilla Firefox

Mozilla has addressed issues causing Firefox to crash on macOS and to freeze with a non-responding blank window when starting on Windows 11 systems.

According to the user who first reported the Windows freeze issue, the bug likely impacts Firefox users running Windows 11 who have also installed this month's KB5023706 cumulative update.

"When Firefox starts it is just a blank window (not a blank web page) with just the Windows min, max, [and] close buttons. If I close the window is says it's not responding and sends a bug report to Microsoft," the bug report filed three days ago reads.

The crash report sent to Microsoft after the Firefox process crashes says the web browser "stopped responding and was closed" because a "problem caused this program to stop interacting with Windows."

The user who reported the issue added that after uninstalling the KB5023706 Windows update, Firefox again started as expected.

While the user report pinned the freeze issues on the KB5023706 update, it’s not clear if that was the stem of the issue or just exacerbated a timing issue originating from a change in behavior making the profile available earlier during startup.

Mozilla has now fixed the browser startup hangs that trigger the freeze issue with the release of Firefox 111.0.1, the latest version released on Tuesday.

"Fixed a bug causing Firefox to freeze on startup for some Windows users," Mozilla says in the Firefox 111.0.1 release notes.

Also fixes a macOS crash

Mozilla also fixed a second bug causing crashes when pinch zooming on macOS systems because of NativelayerCA checks of invalid regions.

"macOS users will experience crashes while pinch-zooming under exceptional circumstances," Mozilla Platform Engineer Brad Werth explained when describing the issue's impact a week ago after a patch was approved.

"This removes an intentional crash we put in to flush out potential invalid pixels. We now believe those pixels are valid, so we no longer want this check, and we certainly don't need to crash."

While a bug report was first filed for this bug three years ago that was tagged as "wontfix," the number of crashes grew exponentially starting on March 15 after the release of Firefox 111.0, which likely prompted a fix.

"Fixed a crash on macOS while pinch-zooming under some circumstances," Mozilla added in the Firefox 111.0.1 changelog.

Update: Revised story and title incorrectly linking the Firefox Windows 11 freeze issue to the KB5023706 update.

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