Manipulation: Don't provide the parser with sloppy table markup

Manipulation: Don't provide the parser with sloppy table markup

While we can reply on parsers that were designed to cope with
malformed syntax to understand what we mean, we shouldn't
intentionally provide bad markup, not all parsers will accept
it.

"Be conservative in what you do, be liberal in what you accept
from others."

(cherry-picked from 99e8ff1baa7ae341e94bb89c3e84570c7c3ad9ea)

Reverts 0ea342a6a6dce793c1b0f14f051c2573f40f4e44

Refs gh-2031
Refs gh-2002
Fixes gh-2493
Closes gh-2499