I also use multiple moniters with LM Cinnamon and they work just fine, but I am sorry to hear it doesn’t work on your machine! KDE doesn’t do it for me aesthetically nor resource-wise, especially on low/mid power laptops while Cinnamon does (although normally I would go for XFCE on low spec hardware). Thankfully we both have the option to choose :)
I think Elmo is supposed to be choosing “healthy sugars” like those in fruit but he can’t resist the pile of sugar instead. Like most sugar junkies :p