Though Poppler isn't a FreeDesktop project is is developed quite closely with Okular, and Okular often depends on features of new-ish Poppler versions. It's also principally maintained by Albert Astals Cid, who also does Okular. It might be a good idea to keep Poppler uo-to-date in a rolling manner in Neon, as if it were a KDE project. See the latest comments in Bug 383651
I've now updated poppler in KDE neon user edition to 22.03.0
And we should get notification of new releases so it can stay up to date
Thanks!