How to select all text fields?.

Hi, I got a form that consists of 3 pages and several docens of text fields, let say I want to apply a change of font, or make them read only, or any other property, how can I do this?, I've tried using Select all-> fields but nothing is selected, only the master page, for some reason.

I've found this explanation of how select all works:

Select All > Select All

Selects all top-level objects, groups, and subforms in the active Layout Editor tab. It also selects the contents of the Script Editor.

However, I'm still unsure about where should I position myself to select everything, tried different approachs, noone worked so far.

Thanks!.