There is a known problem with a class of apps called “Electron” apps which cause a system-wide slowdown on Tahoe. These apps include a private copy of Electron which has a bug (explanation below) which causes this. It has now been fixed but the problem is that many apps haven’t yet incorporated the new version of Electron.
The bug manifests as 100% use of one GPU all the time. Those using a beefy Studio may not notice. Others on MacBooks may be seeing heavy battery use and hearing the fans.
Some popular apps which have been mentioned online as being still unfixed include 1Password, Signal, Figma, Slack, VS Code, Dropbox, Proton Mail and Proton Pass. If you depend on any of these and haven’t yet seen a release from them mentioning it’s been fixed, I recommend you not upgrade to Tahoe yet.
To be clear, this is absolutely not Apple’s fault. There is nothing wrong with Tahoe concerning this and nothing for Apple to fix.
Technical explanation: Chrome was using a private function within AppKit, the part of macOS which handles the GUI. In Tahoe, AppKit now draws the window shadow using different code which assumes that private function was not used. It remembers the shadow has been drawn, but because of what Chrome has done it always appears as if the shadow wasn’t drawn. So AppKit draws the window shadow over and over again forever.
There is a known problem with a class of apps called “Electron” apps which cause a system-wide slowdown on Tahoe. These apps include a private copy of Electron which has a bug (explanation below) which causes this. It has now been fixed but the problem is that many apps haven’t yet incorporated the new version of Electron.
The bug manifests as 100% use of one GPU all the time. Those using a beefy Studio may not notice. Others on MacBooks may be seeing heavy battery use and hearing the fans.
Some popular apps which have been mentioned online as being still unfixed include 1Password, Signal, Figma, Slack, VS Code, Dropbox, Proton Mail and Proton Pass. If you depend on any of these and haven’t yet seen a release from them mentioning it’s been fixed, I recommend you not upgrade to Tahoe yet.
To be clear, this is absolutely not Apple’s fault. There is nothing wrong with Tahoe concerning this and nothing for Apple to fix.
Technical explanation: Chrome was calling a private function within AppKit, the part of macOS which handles the GUI. In Tahoe, AppKit now draws the window shadow using different code which assumes that private function was not called at that time. It remembers the shadow has been drawn, but because of what Chrome has done it always appears as if the shadow wasn’t drawn. So AppKit draws the window shadow over and over again forever.
Oct 03, 2025 at 10:00 PM
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