HTML5 game will not scale well if played with this browser:
It’s samsung default browser.
Screenshot of the problem and the correct one:
https://imgur.com/a/BJB9fXZ
Only our game had this problem, the other were made with cocos2d
To fix it the player need to set their browser to desktop mode.
I have tried different scaling setting. Change width/height to match scene, no changes, and even check the update resolution during the game but none seems to work.
So my friend had been messing with the final build.
To fix it, he said he add
html, body {
width: 100%; height: 100%;
overflow: hidden;
touch-action: none;
}
to the css.
I’m not sure what that means but it works now. He just need to do it every export.
hope it helps. Thanks for the amazing software.
To help your friend tell him he can modify the files in the subfolder resources/GDJS/Runtime of his GDevelop installation directory to not have to modify the files after each export 
Hi I’m been trying to do the same for my HTML5 build, having the exact same issue on samsung browser.
I tried your style code in the index.html… But nothing seems to work.
Would u be able to guide me on this?
Hello, I have the same issue as yours… did you manage to solve it? I tried inserting the code into the index, but nothing happened. I also tried creating an external CSS and calling it in the index, but it doesn’t scale on the Samsung browser. Thanks and goodbye.