How to select the Textbox next to my cursor with the keyboard?

edit

I add some predefined Textboxes with Autotext, by pressing F3, but I would like to instantly edit them, using the keyboard, in order to write fast.

• Shift+F4 focuses the first frame of the document, requiring to press tab until I hit the right frame. Too long.
• Pressing F5 to navigate through the list of document frames is also too long when having mutliple textboxes

Is there a way to focus the textbox next to my cursor, or to focus the textbox I highlighted?