Apple issues second macOS High Sierra Supplemental Update for 2018 MacBook Pro users

Released on Tuesday, the update is aimed at fixing problems with the 2018 MacBook Pro with Touch Bar models, refreshed in July. Apple's support page advises that it is "recommended for all users" of the model.

The first Supplemental Update arrived shortly after the release of the 2018 MacBook Pro range, where it was discovered a software flaw in thermal management software caused excessive throttling under heavy loads. Before the update, the new MacBook Pro versions were found to be slower than earlier versions under throttling, with the patch fixing the issue.

The patch could potentially include a fix for another component, the T2 chip, introduced in the iMac Pro as well as the new MacBook Pro. The T2 sub-processor is intended to handle a number of functions on behalf of the processor, including managing FaceTime camera image quality, regulating boot security, encrypting and decrypting data to flash storage, and powering "Hey Siri vocal prompts for Apple's digital assistant.

Complaints have surfaced in Apple's support forums where a Mac crashes, enters a kernel panic, and either requiring a reboot or restarting itself automatically. A common trait found in error messages is the mention of Bridge OS, an embedded operating system used by the T2 chip, suggesting the problem lies there.

The total file size is 1.3 gigabytes, though specific changes made to the part are not apparent at present. AppleInsider has reached out to Apple for details of the contents.