\input luaotfload.sty

\pdfprotrudechars2 \pdfadjustspacing2

\font\testa=file:texgyrepagella-regular:script=latn at 12pt
\font\testb=file:texgyrepagella-regular:mode=node;script=latn;protrusion=yes;featurefile=opbd.fea;+opbd at 12pt
\testa \input tufte \par
\testb \input tufte \par
\bye