How to change the size of room at run time without changing its size in game maker itself?

Question

I want to change the size of the HTML5 game when it runs on the web page without changing its original size in the game maker studio.

Answer 1

It can be done at run-time but not when in that same room, so make a prep room to start the game in whose creation code sets the width and height using

room_set_width(room_name,width);
room_set_height(room_name,height);
room_goto_next();