I was reminded recently how humour sometimes doesn't work on the interwebs. A sarcastic comment may just look like idiocy when unaccompanied by frantically wiggling eyebrows and other such facial gurning signifiers.
Research suggests this has been the case ever since the very early days of the internet, back in the Middle Ages.
henry_the_2: that @becky_thomas is like right up in my face i mean haha will no-one rid me of him?
fitzurse_etc: we will!!
henry_the_2: hah yeah lol ur my favourite knights
fitzurse_etc: no yeah we totally will!1!
henry_the_2: haha lol yeh right guys ;-)
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henry_the_2: hahh u do no i was just jokg right guys?
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henry_the_2: guys?