dart-sdk/third_party/firefox_jsshell
..
README.google
update.sh

Name: The SpiderMonkey shell.
Short Name: js-shell
URL: https://archive.mozilla.org/pub/firefox/releases/88.0/jsshell/
Version: JavaScript-C88.0
Date: April 19, 2021
License: MPL2, https://www.mozilla.org/en-US/MPL/2.0/

Description:
This directory contains the Mozilla SpiderMonkey shell binaries.

The binaries are used for testing dart code compiled to javascript.