It's fun to see which technical decisions the CSS working group officially consider "mistakes"ย ๐ I agree with most, though not sure how Iย feel about the counter-clockwise directional shorthand ๐ค I'd also never considered the cross-language implication of !important
meaning the opposite in most languages!
Table layout should be sane.
This is also a small slice of history:
Not quite a mistake, because it was a reasonable default for the 90s,
but it would be more helpful since then ifbackground-repeat
defaulted
tono-repeat
.