@rdipardo
Can the column boundary marker actually enforce the column limit, instead of just visually indicating where a break should ideally occur?
Is that not `Document->Line breaking`?
I'm afraid your diagram was more confusing than helpful, the lines you have noted as "ok" are wrapped (see the 180 degree arrow) so they are longer than the marker but by coincidence wrapping has hidden that fact, whilst the "bad" line has a visible exceedance because it hasn't wrapped?