What it feels like to work with Fable:

> Switched to Opus 4.8: Fable 5 has safety measures that flag messages on most cybersecurity or biology topics. They may flag safe, normal content as well. These measures let us bring you Mythos-level capability in other areas sooner, and we're working to refine them. Send feedback or learn more.

Same experience here. The parts of my project that actually could have benefited from Fable's code review got this instead.