You may use this with credit. Steps: Remix the project, or backpack the sprite. Change the text to what you want. Ensure that both costumes are the same except for the blue "OK" before moving on. Some tips and reminders are inside the project, including in-depth instructions and provided scripts on how to make it a choice pop-up (instead of "OK", you could have 2 options such as "cancel" or "continue"). Hope this helps someone! :D Let me know if you find any glitches, and if it works for you.
