Canonical equivalent: Two character sequences are said to be canonical
equivalents if their full canonical decompositions are identical. Canonical equivalence is a Unicode property.
Multiple accents
p.225 for canonical equivalence and multiple accents
Canonical equivalence must be taken into account in rendering multiple accents, so that any two canonically equivalent sequences display as the same.
This is particularly important when the canonical order is not the customary keyboarding order, which happens in Arabic with vowel signs or in Hebrew with points. In those cases, a rendering system may be presented with either the typical typing order or the canonical order resulting from normalization.