Where is the main graphQL component/fragment?

[DPsCoding]

I need some help on data fetching...
My goal is to update the GraphQL structures to add some fields in the query so that I
can read new data added from OTP to Digitransit. I can't understand where is the 'main' graphQL/fragment because there are so many JS with fragments/relay and don't know the relations between all these to mod the code.
Any suggestions? I tried to set many breakpoints in Chromes inspector but it goes too deep in the libraries and you don't understand the sequence of the callstack. Can someone help me? Thanks in advance!