V8 release 7.5

Numeric separators help improve readability for all kinds of numeric literals:

As of Chrome 75, V8 can stream scripts directly from network into the streaming parser, without waiting for the Chrome main thread. While previous Chrome versions had streaming parsing and compilation, the script source data coming in from the network always had to make its way to the Chrome main thread first before being forwarded to the streamer, for historical reasons. In Chrome 75, we connect the network “data pipe” directly to V8, allowing us to read network data directly during streaming parsing, skipping the dependency on the main thread.

Source: v8.dev