We shouldn't be loading the map file in strict mode, because this causes errors with fonts. The cause is the same as https://github.com/gravitystorm/openstreetmap-carto/issues/3086 and the fix is https://github.com/gravitystorm/openstreetmap-carto/pull/3089
We should be calling [Map.fromString](http://mapnik.org/documentation/node-mapnik/3.6/#Map.fromString) somewhere from within the bowels of our code, and need to pass strict : false as part of the options.
Searching through node_modules, this is called by one of mapnik-pool, tilelive-vector, or tilelive-bridge