Crash in Anki stack. Details below

An error occurred. Please start Anki while holding down the shift key, which will temporarily disable the add-ons you have installed.
If the issue only occurs when add-ons are enabled, please use the Tools > Add-ons menu item to disable some add-ons and restart Anki, repeating until you discover the add-on that is causing the problem.
When you’ve discovered the add-on that is causing the problem, please report the issue on the add-on support site.
Debug info:
Anki 2.1.46 (94913ec2) Python 3.8.6 Qt 5.14.2 PyQt 5.14.2
Platform: Mac 10.16
Flags: frz=True ao=True sv=2
Add-ons, last update check: 2021-08-18 18:05:27

Caught exception:
Traceback (most recent call last):
File “aqt/”, line 208, in on_focus_changed
File “aqt/”, line 2495, in call
File “aqt/”, line 749, in on_focus_did_change
File “aqt/”, line 160, in refresh_if_needed
File “aqt/”, line 199, in nextCard
File “aqt/”, line 233, in _get_next_v3_card
File “anki/scheduler/”, line 49, in get_queued_cards
File “anki/_backend/”, line 44, in get_queued_cards
File “anki/_backend/”, line 131, in _run_command