Keymap for operator in Image Editor

I’m trying to set a keymap for my operator in the Image Editor but can’t get it to work.

bl_info = {
    "name": "Custom Operator",
    "category": "Image",
}

import bpy

class CustomOperator(bpy.types.Operator):
    """Object Cursor Array"""
    bl_idname = "image_editor.custom_operator"
    bl_label = "Custom Operator"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self, context):
        print("EXECUTED")
        
        return {'FINISHED'}

# store keymaps here to access after registration
addon_keymaps = []


def register():
    bpy.utils.register_class(CustomOperator)

    # handle the keymap
    wm = bpy.context.window_manager
    # Note that in background mode (no GUI available), keyconfigs are not available either, so we have to check this
    # to avoid nasty errors in background case.
    kc = wm.keyconfigs.addon
    if kc:
        km = wm.keyconfigs.addon.keymaps.new(name='View', space_type='IMAGE_EDITOR')
        kmi = km.keymap_items.new(CustomOperator.bl_idname, 'SPACE', 'PRESS', ctrl=True, shift=True)

        addon_keymaps.append((km, kmi))

def unregister():
    # Note: when unregistering, it's usually good practice to do it in reverse order you registered.
    # Can avoid strange issues like keymap still referring to operators already unregistered...
    # handle the keymap
    for km, kmi in addon_keymaps:
        km.keymap_items.remove(kmi)
    addon_keymaps.clear()

    bpy.utils.unregister_class(ObjectCursorArray)
    bpy.types.VIEW3D_MT_object.remove(menu_func)


if __name__ == "__main__":
    register()

If I use it in the Image Editor pressing space and typing “Custom Operator” it work but the keymap Ctrl + Shift + Space don’t work.
For some reason Ctrl + Shift + Space works I’m in the 3D view even though the space_type is ‘IMAGE_EDITOR’…
I’m not undestanting how this keymap configuration works.