Fable 5.1 is downgrading to Opus 4.8
Status Open
Reported on v2.1.260
Maintainer reply None cached
Activity 0 comments · opened Sep 4, 2026
Bug Description
Fable 5.1 keeps reverting to Opus 4.8. I haven't performed any risky operations against other sources, and there are no attacks taking place. This is a new SaaS product—it is being built with a focus on security and ensuring safety.
Environment Info
- Platform: win32
- Terminal: mintty
- Version: 2.1.260
- Feedback ID: 8100a5e9-e9c5-459f-a12d-5a1fdba935a9
Errors
[{"error":"TelemetrySafeError: VirtualMessageList: itemKeys/messages length desync (keys=214 messages=213 range=[147,214))\n at N$t (B:/~BUN/root/chunk-9tytjqtz.js:36:26122)\n at Sme (B:/~BUN/root/chunk-9tytjqtz.js:36:18954)\n at Ha (B:/~BUN/root/chunk-gcsbr8vy.js:18:20017)\n at Nu (B:/~BUN/root/chunk-gcsbr8vy.js:18:38158)\n at Yh (B:/~BUN/root/chunk-gcsbr8vy.js:18:84182)\n at Tg (B:/~BUN/root/chunk-gcsbr8vy.js:18:83184)\n at Qu (B:/~BUN/root/chunk-gcsbr8vy.js:18:83013)\n at Hh (B:/~BUN/root/chunk-gcsbr8vy.js:18:79547)\n at Ve (B:/~BUN/root/chunk-gcsbr8vy.js:18:6254)\n at Fe (B:/~BUN/root/chunk-gcsbr8vy.js:18:4788)","timestamp":"2026-09-04T13:31:35.257Z"}]