macOS IOUserServer/AppleUserHIDDrivers panic

Initially reported on the forum: https://forums.ankiweb.net/t/anki-interfering-with-mac-hid-restart-crashing/65447

There are reports that suggest that there may be a problem with Anki or the underlying Qt framework that can cause panic/restarts on Mac computers.

- The visible symptom is that the computer panics and restarts after Anki has run for some time.
- The panic error message is `Driver IOUserServer(com.apple.driverkit.AppleUserHIDDrivers-0x...) has crashed too many times`.

Reporting user:
- M1 MacBook Air
- macOS Sonoma 15 (latest as of August 8, 2025)
- Anki Version ⁨25.07.5 (7172b2d2)⁩
- 8BitDo Micro plugged into USB-C
- "Mac restarts unexpectedly (will turn off then restart and say “Your mac restarted because of a problem”), usually while Anki is open. Sometimes it happens mid-review, sometimes while the app is idle in the background."
- The problem started this summer (early July?) and did not previously occur before that. The 8BitDo controller was purchased in early June.

Tested configurations:
- Anki with Contanki, with controller plugged into USB-C: Problem seen.
- Anki in Safe Mode with no add-ons, with controller plugged into USB-C: Problem seen.
- Anki with Contanki, with no controller plugged in: No problem seen.
- Anki not running, controller plugged into USB-C: No problem seen.
- Anki with Contanki, with controller connected via Bluetooth: No problem seen.

So, for this particular user it seems that the problem occurs when the 8BitDo Micro controller is plugged into USB-C and Anki is running, even in Safe Mode.

My suspicions:
1. As I understand it, the Anki desktop app runs a Qt framework web browser to display its windows. Through the Qt framework, gamepad connect/disconnect events are sent to these browser windows. These events are sent even in Anki's Safe Mode when nothing is actively listening for them. Perhaps sending these connect/disconnect events to the browser is somehow causing the panics?
2. I don’t quite fully trust the 8BitDo Micro controller when it is connected by USB. Perhaps the controller is doing something it shouldn't, like rapidly/abnormally connecting and disconnecting?

---

There are other anecdotal reports of the same panic message seen by Anki users in varying circumstances:

https://discussions.apple.com/thread/255915949
January 2025. M4 MacBook Pro "restarts after waking from sleep" with "Driver IOUserServer(com.apple.driverkit.AppleUserHIDDrivers-0x1000025b3) has crashed too many times" panic/restart. User uses Anki with a 8BitDo Micro controller connected via Bluetooth. No devices connected to USB-C ports.

https://community.ankihub.net/t/macbook-crashes-after-syncing-anki/417372
March 2025. Anki user on some sort of MacBook sees "Driver IOUserServer(com.apple.driverkit.AppleUserHIDDrivers-0x100010595) has crashed too many times" panic/restart. User is "using a remote control".

https://discussions.apple.com/thread/256065038
May 2025. Anki user sees the "Driver IOUserServer(com.apple.driverkit.AppleUserHIDDrivers-0x1000010ea) has crashed too many times" panic/restart upon M3 MacBook Air sleep, started after upgrade to macOS 15.5. "The only thing I plug in is the charger," so no USB devices plugged in. It is unclear if a game controller might be being used through Bluetooth. The last kernel extension loaded at the moment of panic was com.apple.driver.AppleGameControllerPersonality.

Start by reviewing the linked forum report and comparing the listed configurations: Anki with and without Contanki, Safe Mode, and USB-C versus Bluetooth. The issue mentions no source files, tests, or entry points; progress would require reproducing the macOS panic and determining whether Anki, the Qt framework, or the controller is responsible.

Written by the indexing model from the issue text.