The first definition the OED gives of scumbag is “condom”, from “scum” meaning “foam” or “froth”, and by extension “semen”. This usage dates back to 1967. “Scumbag” as an insult shows up in 1971.
Giving opinions on matters outside of one’s knowledge.
(HT Pinky and the Brain on DVD; checked at the OED.)
I’ve started learning this
One thing I’ve always liked about books is the way typesetters sometimes render the first letter differently from the others, usually several times larger, and with the paragraph flowing around it. Sometimes, the first line or the first few words of the first paragraph are also rendered in small caps. I’ve finally figured out how to do this with CSS: