text/html; firefox '%s'; test=test -n "$DISPLAY"; needsterminal;
text/html; w3m -I %{charset} -T text/html; copiousoutput;
text/plain; less -N %s; copiousoutput;
application/json; jq . %s | less -N; copiousoutput;
application/pdf; firefox '%s'
application/zip; unzip -p '%s' | less -N
application/gzip; gunzip -c '%s' | less -N
image/png; feh '%s'
image/jpg; feh '%s'
image/jpeg; feh '%s'
image/gif; feh '%s'