There is a typo in second bullet point where it says:

Transactions will fail is the client is offline, they cannot use cached data

where it should be if rather then is after transactions will fail

Link: https://firebase.flutter.dev/docs/firestore/usage#transactions

Google suggests enabling gzip compression before transferring files over the network:

In order to receive a gzip-encoded response you must do two things: Set an Accept-Encoding header, and modify your user agent to contain the string gzip. Here is an example of properly formed HTTP headers for enabling gzip compression:

Acc