TL;DR: A new tile-based refiner and upscaler named Hildegard has been released for FLUX.2 Klein, leveraging a spatial-context LoRA to maintain global coherence.
Summary: Developer 42lux released Hildegard, a tile-based refiner and upscaler designed for the FLUX.2 Klein (9B) model. The system constructs three reference latents per tile consisting of the tile itself, a 3x3 neighbor position map, and a thumbnail of the full image. A custom LoRA processes these latents together so the model understands the global context of each tile during the upscale process.
Why it matters: This release provides a modern alternative to Ultimate SD Upscale that prevents seams and inconsistencies in high-resolution FLUX generations. Builders should install the nodes via Comfy Manager to integrate high-fidelity upscaling into their image generation workflows.
Source: r/stablediffusion