diff --git a/src/constants.rs b/src/constants.rs
index aaa06eb..2d10747 100644
--- a/src/constants.rs
+++ b/src/constants.rs
@@ -4,7 +4,7 @@ pub const LISTEN_ADDRESSES_V6: &[&str] = &["[::]"];
 // pub const HTTPS_LISTEN_PORT: u16 = 8443;
 pub const PROXY_TIMEOUT_SEC: u64 = 60;
 pub const UPSTREAM_TIMEOUT_SEC: u64 = 60;
-pub const TLS_HANDSHAKE_TIMEOUT_SEC: u64 = 3;
+pub const TLS_HANDSHAKE_TIMEOUT_SEC: u64 = 15; // default as with firefox browser
 pub const MAX_CLIENTS: usize = 512;
 pub const MAX_CONCURRENT_STREAMS: u32 = 64;
 pub const CERTS_WATCH_DELAY_SECS: u32 = 60;