FirstAid is a simple PDF viewer based on libpoppler - https://poppler.freedesktop.org/
Design goal is the use as a help viewer deployable with your application to show the online help PDFs and jump to named locations to provide context sensitive help.
If you look for a full-fledged PDF viewer, head over to other projects like Okular - https://okular.kde.org/
Compilation requirements are Qt 6.x and a recent libpoppler and dependencies of that like FreeType/FontConfig/...
FirstAid is based on the Qt 5 demo program of libpoppler and licensed like libpoppler under GPLv2+.
All contributions shall happen under that license.