When I execute a grpcurl command to execute a call, and I provide multiple proto files that each import the same common.proto, then I get the error :

Failed to process proto source files.: given files include multiple copies of "common.proto" 

This happens only with 1.8.8 (not with 1.8.6, nor 1.8.7)
I believe this is common for multiple proto files to import the same utilities, and grpcurl should not enforce that condition