QPDF 12.4.2: Apache-2.0; see QPDF-LICENSE.txt and QPDF-NOTICE.md.
zlib 1.3.2: zlib license; see zlib-LICENSE.txt.
Independent JPEG Group libjpeg 9f: IJG terms; see libjpeg-README.txt.
The exact Emscripten port recipes are pinned by Emscripten commit aeb67926e7de656da38bc807d83050af93578758.