I just realized that none of our current unit-tests cover this particular part of the Page Label parsing code, hence this patch adjusts an existing test PDF to include a "St" entry in the Page Label dictionary.
JavaScript
CFFParser_parseDict
new {Name,Cmd}
{Name,Cmd}.get
beforeAll
afterAll
isExternalLinkTargetSet
Lexer_getName
Name
primitives.js
isDict