now, I do see *.rdd files in userdata/persistence. each one with 116.408 Bytes
Unfortunately I don’t get any data with the rest service but this is probably user error since I don’t get data on the other machine with working charts as well.
Querying the api for persistence service “rrd4j” returns no items on both machines.
the fontconfig sounds likely, Synology DSM seems to do some things differently than the common linux distro
Looking into moving this to the raspberry now