We have different editing strategies for different models, e.g the SD endpoint that rewrites the file top to bottom and more targeted edits like find_replace. The UX is currently very optimised for the slowing SD endpoint, e.g

• we disable squiggles because while the file is rewritten (asynchronously) it is often in a weird intermediate garbage state
• we disable auto-save, also because of intermediate garbage state that we don't want to be picked up by external build tools like test runners
• we highlight the last edited line
• we show an animation for the duration of the request

This is great and works very well for SD endpoint cases but isn't the best for replace editing. There we can remove some of the mitigation (disable squiggles/auto-save) and tweak the animation a little more