I've done a small amount of reading and it seems this isn't possible with square up website edit?
Hey there @Blaze-_-drags,
Thanks for reaching out to us and welcome to the Seller Community! 👋
You would be correct here, at this stage any changes made to your site will be visible on both desktop and mobile versions. While you can preview your site in either version, we do not yet support the ability to edit the two versions separately.
Let me know if any other questions come up for you!
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