maxscale-2.3 has broken the maxscale_exporter which is provided at: https://github.com/mariadb-corporation/maxscale_exporter
The issue is the maxinfo (port 8003) HTTP interface is now returning all values as strings where they used to be returned as integers in the JSON return structure. If would be preferable if the maxinfo returned JSON was kept as it was.
See the attached maxinfo-2.2.out and maxinfo-2.3.out for the difference in the JSON return formats. At least, the maxscale-2.3 output does not match the JSON output in the documentation at https://mariadb.com/kb/en/mariadb-maxscale-23-maxinfo-plugin/