diff --git a/libavformat/httpauth.c b/libavformat/httpauth.c
index 3f90975ff3..dbe3eff48f 100644
--- a/libavformat/httpauth.c
+++ b/libavformat/httpauth.c
@@ -224,8 +224,11 @@ static char *make_digest_auth(HTTPAuthState *state, const char *username,
     av_strlcatf(authstr, len, ",nonce=\"%s\"",     digest->nonce);
     av_strlcatf(authstr, len, ",uri=\"%s\"",       uri);
     av_strlcatf(authstr, len, ",response=\"%s\"",  response);
+
+    // we are violating the RFC and use "" because all others seem to do that too.
     if (digest->algorithm[0])
         av_strlcatf(authstr, len, ",algorithm=\"%s\"",  digest->algorithm);
+
     if (digest->opaque[0])
         av_strlcatf(authstr, len, ",opaque=\"%s\"", digest->opaque);
     if (digest->qop[0]) {