When I extend a class, as shown here:
export class AbstractType extends Phaser.GameObjects.Sprite
and try to add a subclass of that type(AbstractType) into a container,
symbols.add(symbol)
I get the following error:
TypeError: gameObject.once is not a function
at Container.addHandler (/Users/schwarzj/Desktop/symphonymathhtml5/node_modules/phaser/dist/phaser.js:57689:1)
at Object.Add (/Users/schwarzj/Desktop/symphonymathhtml5/node_modules/phaser/dist/phaser.js:100986:1)
at Container.add (/Users/schwarzj/Desktop/symphonymathhtml5/node_modules/phaser/dist/phaser.js
