Q:

TinyMCE default font size

How can I set the default font size of tinyMCE , I've a tinyMCE editor and I tried all the things to change the  text-size to 14px and it always shows 10px. I'm using rails 3.1 and tinymce 
major Version: '3', and minor Version: '4.4'.
I changed tinymce/themes/advanced/skins/default/content.css font-size to 14px
I even add 
tinyMCE.init({
    theme_advanced_font_sizes: "10px,12px,13px,14px,16px,18px,20px",
    font_size_style_values: "12px,13px,14px,16px,18px,20px",
});

and
body, td, pre { color: #000; font-family: Verdana, Arial, Helvetica, sans-serif; 
    font-size: 14px; margin: 8px; }

A:

You can load a custom stylsheet for the textarea:
tinyMCE.init({
  content_css : "custom_content.css"
});

In there you can style your fonts like on a normal page.

A:

You need to empty you browser's cache. Sometimes you have to do that to ensure TinyMCE is not using an older file.
[As @Jona and @Nikola said, please make sure you are referencing a new CSS flle].

