>>53671335on windows
>C:\Users\<your name>\AppData\LocalLow\pokemon\Pokemon TCG Live\config-cache\config-cache.jsonThat's where the game stores pack data it downloads from the server. It's hard to read but you can find drop rates of any pack you have opened so far on that computer.
You would take the content string and save it to a new json file so that you can open it in whatever json viewer you have.