谷歌开发工具中的缓存控制

Question

我正在玩Chrome Dev Tools，我对缓存控制的使用有疑问。

我有一个app.js和application.css的简单应用程序，当我检查工具栏中的禁用缓存时，两个资源都从服务器下载，但当我取消选中它时，app.js不会再次下载它位于浏览器缓存中，但是再次下载了application.css。

我检查了响应头，希望看到一个缓存控制：application.css的no-cache但是......它不在那里。实际上，关于application.css和app.js的缓存控制的响应头中的信息是相同的：没有信息。

任何人都知道或不知道为什么会这样？

由于

编辑：请求和响应标头

"request": {
          "method": "GET",
          "url": XXXXXXXXXX,
          "httpVersion": "HTTP/1.1",
          "headers": [
            {
              "name": "Accept-Encoding",
              "value": "gzip, deflate, sdch, br"
            },
            {
              "name": "Host",
              "value": XXXXXXXXXX
            },
            {
              "name": "Accept-Language",
              "value": "es-ES,es;q=0.8"
            },
            {
              "name": "Upgrade-Insecure-Requests",
              "value": "1"
            },
            {
              "name": "User-Agent",
              "value": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.133 Safari/537.36"
            },
            {
              "name": "Accept",
              "value": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8"
            },
            {
              "name": "Referer",
              "value": XXXXXXXXXX
            },
            {
              "name": "Cookie",
              "value": XXXXXXXXXX
            },
            {
              "name": "Connection",
              "value": "keep-alive"
            },
            {
              "name": "Cache-Control",
              "value": "max-age=0"
            }
          ],
          "queryString": [],
          "cookies": [
            {
              XXXXXXXXXX
            }
          ],
          "headersSize": 527,
          "bodySize": 0
        },
        "response": {
          "status": 200,
          "statusText": "OK",
          "httpVersion": "HTTP/1.1",
          "headers": [
            {
              "name": "Date",
              "value": "Fri, 21 Apr 2017 08:41:14 GMT"
            },
            {
              "name": "Last-Modified",
              "value": "Sun, 16 Apr 2017 11:17:04 GMT"
            },
            {
              "name": "Server",
              "value": "nginx/1.10.1"
            },
            {
              "name": "ETag",
              "value": "\"58f352b0-7ad\""
            },
            {
              "name": "Content-Type",
              "value": "text/html"
            },
            {
              "name": "Connection",
              "value": "keep-alive"
            },
            {
              "name": "Accept-Ranges",
              "value": "bytes"
            },
            {
              "name": "Content-Length",
              "value": "1965"
            }
          ],