itch.io

I think there is a way to do spoliers! If you go to the description of your game, click the angle brackets for HTML in the formatting bars, and add

<details>

<summary>SPOILERS:</summary>

this is where spoilers go

</details>

to wherever you want the spoiler and then click the angle brackets again, it'll add a little dropdown menu that needs to be clicked before people see the "this is where spoilers go" part!