ok i looked it up and apparently if you go to your profile settings and enable enable “Prefer Markdown input where available”, then you can type spoilers by using:
<details><summary>Spoiler alert</summary>You can click on this text to reveal more text</details>
to get:
Spoiler alert
You can click on this text to reveal more texthowever then you get stuff like
2*4*6
turning into 246
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