Fix image generation: default to SDPA attention backend

modules/image_models.py

@@ -129,7 +129,7 @@ def load_image_model(model_name, dtype='bfloat16', attn_backend='sdpa', cpu_offl
 
         modules = ["transformer", "unet"]
 
-        # Set attention backend
+        # Set attention backend (diffusers defaults to native/SDPA)
         if attn_backend == 'flash_attention_2':
             for name in modules:
                 mod = getattr(pipe, name, None)

modules/shared.py

@@ -364,7 +364,7 @@ settings = {
     'image_llm_variations_prompt': 'Write a variation of the image generation prompt above. Consider the intent of the user with that prompt and write something that will likely please them, with added details. Output only the new prompt. Do not add any explanations, prefixes, or additional text.',
     'image_model_menu': 'None',
     'image_dtype': 'bfloat16',
-    'image_attn_backend': 'flash_attention_2',
+    'image_attn_backend': 'sdpa',
     'image_cpu_offload': False,
     'image_compile': False,
     'image_quant': 'none',