title: Selenoid: why can't I run specific browser version?
body: <p>I have the following configuration file browsers.json:</p>
  
  <pre><code>{
      "chrome": {
          "default": "69.0",
          "versions": {
              "60.0": {
                  "image": "selenoid/chrome:60.0",
                  "port": "4444",
                  "path": "/",
                  "tmpfs": {
                      "/tmp": "size=128m"
                  }
              },
              "69.0": {
                  "image": "selenoid/chrome:69.0",
                  "port": "4444",
                  "path": "/",
                  "tmpfs": {
                      "/tmp": "size=128m"
                  }
  },
      "firefox": {
          "default": "60.0",
          "versions": {
              "50.0": {
                  "image": "selenoid/firefox:50.0",
                  "port": "4444",
                  "path": "/wd/hub",
                  "tmpfs": {
                      "/tmp": "size=128m"
                  }
              },
              "60.0": {
                  "image": "selenoid/firefox:60.0",
                  "port": "4444",
                  "path": "/wd/hub",
                  "tmpfs": {
                      "/tmp": "size=128m"
          }
              }
          }
      },
  </code></pre>
  
  <p>In tests I have the following code:</p>
  
  <pre><code>capabilities = {
                  "browserName": "chrome",
                  "version": "60.0"
              }
              options = webdriver.ChromeOptions()
              options.add_argument('--ignore-certificate-errors')
              options.add_argument('--no-sandbox')
              self.driver = webdriver.Remote(
                  command_executor="http://localhost:4444/wd/hub",
                  desired_capabilities=capabilities, options=options)
  </code></pre>
  
  <p>question: why can't I run specific browser version?
  It gives me exception:</p>
  
  <pre><code>WebDriverException: Message: Requested environment is not available
  </code></pre>
  
  <p>If I don't specify version in capabilities, test runs successfully.</p>