Under macOS 26 Tahoe: huge lag with Electron apps
The WindowServer task in the new macOS runs amok by overriding an AppKit API in Electron. Apparently there is a fix, but it needs to be installed.
An electron (symbolic image).
(Image: Pavel Ignatov/Shutterstock.com)
Users of macOS 26 alias Tahoe are complaining about system slowdowns in connection with certain apps. The reason is apparently an incompatibility of the operating system with the Electron framework, which is used by well-known applications such as Discord or VS Code. An override hack of a private AppKit API is apparently used there to generate certain window effects. This in turn collides with macOS 26 and its implementation of the WindowServer task, which is responsible for the macOS window display, according to the Electron project's GitHub forum.
Edge conflict between Electron and macOS 26
A fix already exists within Electron: it is in versions v39.0.0-alpha.7, v38.2.0, v37.6.0, and v36.9.2, but developers still have to update the framework themselves, which can take a few days—if they are aware of the problem at all. In practice, the bug means that it is enough that an Electron app is running and has not been minimized. It can slow down the whole system even on a fast Apple Silicon Max chip. Although it initially appears that the CPU and GPU load is low, a redraw behavior of WindowServer ensures that the graphics cores are temporarily overloaded. This can be noticed by slow scrolling.
Videos by heise
If several Electron apps are open, it gets worse. If Chrome is open and an Electron app is minimized, the issue seems to go away, according to Hacker News, as developer Michael Tsai summarizes in his blog. Electron seems to try to use so-called custom corner masks for Vibrant views, which in turn do not please the new WindowServer in Tahoe, so he is trying to regenerate them. Apple had made the edges in Tahoe much rounder.
Passwords problem in Electron fixed in macOS 26.0.1
Apple also released macOS 26.0.1 this week, which provides some bug fixes. According to Ricky Mondella, there is another bug fix in connection with Electron apps and Chromium browsers: A bug in the AutoFill area should no longer occur.
This could also slow down apps, as it led to incorrect handling of event taps. AutoFill is used to fill in passwords. Apple provides details on the feature for developers in its documentation for developers.
Empfohlener redaktioneller Inhalt
Mit Ihrer Zustimmung wird hier ein externer Preisvergleich (heise Preisvergleich) geladen.
Ich bin damit einverstanden, dass mir externe Inhalte angezeigt werden. Damit können personenbezogene Daten an Drittplattformen (heise Preisvergleich) übermittelt werden. Mehr dazu in unserer Datenschutzerklärung.
(bsc)
