PSA: if you want to stay on my friends list you're gonna have to avoid slurs, especially ableist slurs, because there are only so many I can take. If you don't care that use of these words/concepts hurts me and many other people, you are bad at empathy and I don't want to be your friend. I am happy to give you the benefit of the doubt and point this out once, maybe twice, possibly more if you respond well when I mention it and seem to not have realized, but really, you need to do the work of thinking about your language.
This includes: [TW: ableist slurs]
stupid, lame, mong, idiot, dumb, idiot, retard, derp, mongoloid, and all variations, such as stupidity, monging, idiotic, dumbass, retarded, derpy, 'special', short bus, etc.
---- end slur list-----
ANYTHING that refers to the idea of "less intelligence" in a non-positive way.
Also, anything that implies mental illness is inherently bad, or uses mental illness as adjectives for their lives or for things they don't like. for instance, "the weather is bipolar" "my mother-in-law is crazy" "I'm totally manic" (if you don't actually experience the mental state of mania, and no that doesn't just mean hyper and happy).