How can I quickly convert all text to outlines in a 44-page InDesign document?

This is a very bad idea for so many reasons, and if you are being asked to do this by a supposedly "professional" printer, I'd look for somone else. Asking for outlines in this day and age is downright archaic.

There are on a few processes I have dealt with that still need to have text converted to outlines, e.g. flexography, CNC processes, etc, none of which I doubt applies here for a 44-page book.

The other issue is that outlines from improperly-made variable fonts have been known to cause problems, especially with CNC machines, as the letter forms are layered pieces of glyphs as opposed to a united single shape.

Outlining in Acrobat is possible, yes, but is affected by this variable font issue also.

You can convert fonts to outline in Acrobat with far better results.

Hi @Frans van der Vleuten , Before this thread gets locked see this:

https://community.adobe.com/t5/indesign-discussions/outline-text-with-bullets-numbering/td-p/9901724/page/4

Is this for an onlne printer? Some online printers will ask for outlines as a hedge against missing fonts, but in Acrobat you can check to make sure the fonts are included via Document Properties>Fonts.

Never outline text in InDesign as it is an absolute no-go. This function is only for graphic purposes. You will get a lot of problems which were often discussed here. 

If you need outlines you can do it in Acrobat Pro, Print Production, Preflight with a singlr click, even with PDFs with thousands of pages without any problem. 

For executing the script you can look at the following article

https://creativepro.com/how-to-install-a-script-in-indesign-that-you-found-in-a-forum-or-blog-post/

To be extra safe make a copy of your document before executing the script

-Manan

The following one liner should do the trick