Matt, I just 'agreed' to reset - these are minecraft launcher settings as far as I experienced, and minecraft started ok after that (from the old launcher).
However, the issue is now fixed and I can launch with the new launcher.
Sam - you are a star - this works. Great temporary fix 🙂 Thanks (I can now relax, I had braced myself for the melt-down of my ADS boy who will come home from school soon)!
Matt, I just 'agreed' to reset - these are minecraft launcher settings as far as I experienced, and minecraft started ok after that (from the old launcher).
However, the issue is now fixed and I can launch with the new launcher.