Log Message:
these options does not exist
 --disable-elf-dynstr-gc
 --disable-installer
 --disable-javaxpcom
 --disable-mochitest
 --disable-pedantic
 --enable-canvas
 --enable-crypto
 --enable-mathml
 --enable-pango
 --enable-svg
 --with-system-ply
you can see it:
 cd /usr/pkgsrc/www/firefox/work/firefox-48.0
 ./configure --help