Fix custom lookback in safari (#2387)
Fix custom lookback in safari (#2387)


openzipkin/zipkin,adriancole/zipkin,twitter/zipkin,openzipkin/zipkin,openzipkin/zipkin,adriancole/zipkin,twitter/zipkin,openzipkin/zipkin,twitter/zipkin,openzipkin/zipkin,adriancole/zipkin,adriancole/zipkin,twitter/zipkin