Patch-Source: https://github.com/arut/nginx-dav-ext-module/pull/46
--
From a44e56c57e5fcf6b769f816f726199c52a8dca8c Mon Sep 17 00:00:00 2001
From: Alexey Lubimov <avlubimov@gmail.com>
Date: Tue, 20 Aug 2019 14:40:43 +0300
Subject: [PATCH] fix DAV class from 2 to 1,2 (like apache)

---
 ngx_http_dav_ext_module.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/ngx_http_dav_ext_module.c b/ngx_http_dav_ext_module.c
index 0d6d067..bb5ead4 100644
--- a/ngx_http_dav_ext_module.c
+++ b/ngx_http_dav_ext_module.c
@@ -502,8 +502,16 @@ ngx_http_dav_ext_content_handler(ngx_http_request_t *r)
         }
 
         ngx_str_set(&h->key, "DAV");
-        h->value.len = 1;
-        h->value.data = (u_char *) (dlcf->shm_zone ? "2" : "1");
+
+        if (dlcf->shm_zone) {
+            h->value.len = 3;
+           h->value.data = (u_char *) "1,2";
+        } 
+        else {
+           h->value.len = 1;
+           h->value.data = (u_char *) "1";
+        }
+
         h->hash = 1;
 
         h = ngx_list_push(&r->headers_out.headers);