chromium/extensions/test/data/policy_violation/README.md

# Policy Violation Test Data
The files in this directory assist with manual testing policy-violating
extension behavior.

- ext.crx: A small example extension.
- ext.pem: A private key corresponding to ext.crx.
- rsp.py: A python3 script that runs a server on port 8080 and serves a canned
response to POST queries indicating that ext.crx violates policy.

ext.crx can be regenerated by unpacking it, modifying files, and then repacking
it using Chrome's "pack extension" function at chrome://extensions. As long as
ext.pem is reused, the extension ID will not change and rsp.py need not be
modified.