5.18 How to change magnification factor when using dvisvgm with make4ht?

When using the command

make4ht -ulm default -e ~/new.mk4 -c ~/nma.cfg -f html5+dvisvgm_hashes filename.tex "htm,0,pic-align,notoc*,p-width,svg"
 

Then make4ht defaults to using these options dvisvgm -v4 -n --exact -c 1.15,1.15

These options are set in this file /usr/local/texlive/2018/texmf-dist/scripts/make4ht/extensions/dvisvgm_hashes.lua

To change them, add this to your .mk4 file (Thanks to Michal for this hint)

filter_settings "dvisvgm_hashes" { 
  options = "-n --exact -c 1.5,1.5" 
}