3 files changed, 6 insertions, 3 deletions
diff --git a/lib/vtls/gtls.c b/lib/vtls/gtls.c
index 844be2de1..cbbb61f76 100644
--- a/lib/vtls/gtls.c
+++ b/lib/vtls/gtls.c
@@ -763,7 +763,8 @@ gtls_connect_step1(struct connectdata *conn,
     gnutls_datum_t protocols[2];
 
 #ifdef USE_NGHTTP2
-    if(data->set.httpversion >= CURL_HTTP_VERSION_2) {
+    if(data->set.httpversion >= CURL_HTTP_VERSION_2 &&
+       (!SSL_IS_PROXY() || !conn->bits.tunnel_proxy)) {
       protocols[cur].data = (unsigned char *)NGHTTP2_PROTO_VERSION_ID;
       protocols[cur].size = NGHTTP2_PROTO_VERSION_ID_LEN;
       cur++;
diff --git a/lib/vtls/nss.c b/lib/vtls/nss.c
index cd0138930..0097caf01 100644
--- a/lib/vtls/nss.c
+++ b/lib/vtls/nss.c
@@ -1992,7 +1992,8 @@ static CURLcode nss_setup_connect(struct connectdata *conn, int sockindex)
     unsigned char protocols[128];
 
 #ifdef USE_NGHTTP2
-    if(data->set.httpversion >= CURL_HTTP_VERSION_2) {
+    if(data->set.httpversion >= CURL_HTTP_VERSION_2 &&
+       (!SSL_IS_PROXY() || !conn->bits.tunnel_proxy)) {
       protocols[cur++] = NGHTTP2_PROTO_VERSION_ID_LEN;
       memcpy(&protocols[cur], NGHTTP2_PROTO_VERSION_ID,
           NGHTTP2_PROTO_VERSION_ID_LEN);
diff --git a/lib/vtls/openssl.c b/lib/vtls/openssl.c
index dbee36929..11419f488 100644
--- a/lib/vtls/openssl.c
+++ b/lib/vtls/openssl.c
@@ -2057,7 +2057,8 @@ static CURLcode ossl_connect_step1(struct connectdata *conn, int sockindex)
     unsigned char protocols[128];
 
 #ifdef USE_NGHTTP2
-    if(data->set.httpversion >= CURL_HTTP_VERSION_2) {
+    if(data->set.httpversion >= CURL_HTTP_VERSION_2 &&
+       (!SSL_IS_PROXY() || !conn->bits.tunnel_proxy)) {
       protocols[cur++] = NGHTTP2_PROTO_VERSION_ID_LEN;
 
       memcpy(&protocols[cur], NGHTTP2_PROTO_VERSION_ID,