I gotta be real with you, this aint that good
First of all went going to cahnge the color of the icons most of the time there is noticable red lines in it, this can be cleary seen with the black colors, this can be more clearly seen with the cat icon (or as I like to call it, the juniper icon) where if you make your icon all black its clearly seen, second some colors with specific icons can make the game not work went you press play leaving you into a black screen where you can do nothing but look at it and refesh the page also why is the default colors red and blue? that conbination of colors is horrible and its too risky to change the color scheme sinse you dont know wish colors could lead to the game breaking into the black screen metioned earlier.
now the level, its not that good, first of all why does it switch to green and red for the first two spike jumps and then come back to normal, the part where the text is turns into a unreadable texture mess, also sometimes it skips attemps like on how went you are in 17 attemps and you die it skips to 19 attemps although thats about it for the level, you shoud also add spacebar and arrow key support sinse clicking can be hard
the editor is quite bad, the first thing you would notice is how the arrows to move around your level dont match up at all with the whole green and whie aestetic the normal geometry dash editor haves, there are many empty spaces in the editor, you can also build on the floor wish is not really a good thing and shoud be fixed, there is also no way to play test your levels inside the editor, you shoud add a way to play test it inside the editor and not having to enter your own level, that way its more combinient, it could save time, it would be easier to correct mistakes and it would be overall better
tl;dr:game is shit with a lot of bugs and it shoud be fixed