In the advanced tab in editing the theme I put in the font field "Open Sans Condensed"

Joomla render

<link href="https://fonts.googleapis.com/css?family=Open Sans Condensed" rel="stylesheet" />
<style>
h1, h2, h3, h4, h5, h6, .site-title {
   font-family: 'Open Sans Condensed', sans-serif;
}
</style>

Google expect
https://fonts.googleapis.com/css?family=Open+Sans+Condensed:300 in link
acording to https://fonts.google.com/specimen/Open+Sans+Condensed

I tried to put "Open Sans Condensed:300" to correct the URL, but joomla render

<link href="https://fonts.googleapis.com/css?family=Open Sans Condensed:300" rel="stylesheet" />
<style>
h1, h2, h3, h4, h5, h6, .site-title {
   font-family: 'Open Sans Condensed:300', sans-serif;
}
</style>

In this second case the link is correct but the font-family is wrong