"Use Formatting In Current Editor" is not present

I figured out how to change the editor font, but although youtube.com/watch?v=66CnHtgjlRQ shows a “Use Formatting In Current Editor” button, that button is not present in my version (Windows 1.9.9)

How can I apply the formatting to my existing editors? Ideally all at once?

For Windows:
To set a default font for an entire document got to Tools>Options>Editor and in the top right hand box is a graphical representation of a format screen with text. This is titled Default main text attributes. Click on the blue A to set your default font, font size etc.
This will ensure all new documents are using your preferred font settings.

If you need to also change existing text documents, you can do so via the following method:

  1. Click anywhere in the binder area to make the area active. Go to Edit>Select All. This should select everything in your binder.
  2. Go to Documents>Convert>Formatting to default text style… A box pops up. Select what you need i.e. just fonts and then hit OK.