id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
37054	Precompute the Referrer-Policy header value during middleware initialization	Mason Lyons	Mason Lyons	"The SecurityMiddleware runs on every Django request and adds security headers to responses. The original `process_response()` method constructs the Referrer-Policy header by performing string operations on every request:

{{{
def process_response(self, request, response):
    # ... other headers ...
    if self.referrer_policy:
        # Support a comma-separated string or iterable of values to allow
        # fallback.
        response.headers.setdefault(
            ""Referrer-Policy"",
            "","".join(
                [v.strip() for v in self.referrer_policy.split("","")]
                if isinstance(self.referrer_policy, str)
                else self.referrer_policy
            ),
        )
}}}

Move the string manipulation to `__init__()` where it runs once when the middleware is initialized, storing the pre-computed value for use in `process_response()`
"	Cleanup/optimization	closed	HTTP handling	6.0	Normal	wontfix	middleware	Mason Lyons	Unreviewed	1	0	0	0	0	0