Pretty easy to use, on the last updated ForgeWebUI, copy this model from BFL HF in the /models/Stable-diffusion folder :
Edit : also support the FP8 model https://huggingface.co/Kijai/flux-fp8/blob/main/flux1-dev-fp8-e4m3fn.safetensors
Here are my settings on a A2000 8Gb mobile GPU
And Flux Dev Loras are also working.

