Can't read player.dat file on web

[Frogperson]

I'm trying to read a Minecraft playerdata file using Flutter Web, and I'm running into a couple issues:

1. Apparently the file I was trying to read was compressed as gzip. Digging into the code, I saw this comment:
   "On JS platforms, this does nothing, as it requires converters from 'dart:io'."
   Not a huge problem for me though, as I can detect the compression type and just use https://pub.dev/packages/archive which does support web.

2. After decompressing, I'm getting "Error: Unsupported operation: Int64 accessor not supported by dart2js." which is from this line: https://github.com/spnda/dart_minecraft/blob/main/lib/src/utilities/readers/_byte_reader.dart#L61
   I also found this related issue: Int64 and Uint64 methods and types are not supported in Dart2JS's typeddata dart-lang/sdk#10275
   Is there anything we can do about this?