diff --git a/indra/llcorehttp/llhttpconstants.cpp b/indra/llcorehttp/llhttpconstants.cpp
index 40d6c7506c..7a671543d9 100755
--- a/indra/llcorehttp/llhttpconstants.cpp
+++ b/indra/llcorehttp/llhttpconstants.cpp
@@ -100,6 +100,7 @@ const std::string HTTP_IN_HEADER_LOCATION("location");
const std::string HTTP_IN_HEADER_RETRY_AFTER("retry-after");
const std::string HTTP_IN_HEADER_SET_COOKIE("set-cookie");
const std::string HTTP_IN_HEADER_USER_AGENT("user-agent");
+const std::string HTTP_IN_HEADER_X_CONTENT_TYPE_OPTIONS("x-content-type-options");
const std::string HTTP_IN_HEADER_X_FORWARDED_FOR("x-forwarded-for");
const std::string HTTP_CONTENT_LLSD_XML("application/llsd+xml");
@@ -122,6 +123,7 @@ const std::string HTTP_CONTENT_IMAGE_BMP("image/bmp");
const std::string HTTP_NO_CACHE("no-cache");
const std::string HTTP_NO_CACHE_CONTROL("no-cache, max-age=0");
+const std::string HTTP_NOSNIFF("nosniff");
const std::string HTTP_VERB_INVALID("(invalid)");
const std::string HTTP_VERB_HEAD("HEAD");
diff --git a/indra/llcorehttp/llhttpconstants.h b/indra/llcorehttp/llhttpconstants.h
index 583f9fbcb7..71c1dfa173 100755
--- a/indra/llcorehttp/llhttpconstants.h
+++ b/indra/llcorehttp/llhttpconstants.h
@@ -190,6 +190,7 @@ extern const std::string HTTP_IN_HEADER_LOCATION;
extern const std::string HTTP_IN_HEADER_RETRY_AFTER;
extern const std::string HTTP_IN_HEADER_SET_COOKIE;
extern const std::string HTTP_IN_HEADER_USER_AGENT;
+extern const std::string HTTP_IN_HEADER_X_CONTENT_TYPE_OPTIONS;
extern const std::string HTTP_IN_HEADER_X_FORWARDED_FOR;
//// HTTP Content Types ////
@@ -215,5 +216,6 @@ extern const std::string HTTP_CONTENT_IMAGE_BMP;
//// HTTP Cache Settings ////
extern const std::string HTTP_NO_CACHE;
extern const std::string HTTP_NO_CACHE_CONTROL;
+extern const std::string HTTP_NOSNIFF;
#endif
diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index aefb6d32dc..531bac5b53 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -17237,9 +17237,9 @@ Change of this parameter will affect the layout of buttons in notification toast
Use24HourClock