Sorry if this has been posted before, but forum searches did not result in any method that worked for me.

Being too thick to use MaGog , all I got was a list of numbers......

I use this way instead.

Open the GOG page showing your owned games, right click and save as HTML - WEB PAGE COMPLETE.

The "HTML - WEB PAGE COMPLETE" is important as the other way does not show your games.

Do this for each page of games.

Open the resulting file in a word processor , not a text editor. I used Libre Office.

Your list of games is about half way down, so delete all text above your first game and then all text after the last.

If your list has "UPDATED! This game has updates waiting for you" between each game title, use the FIND or SEARCH function to select all instances of that text and delete.

I had multiple game pages, so I saved and edited each one, then joined the lists together in one document.

Long winded, but quicker than it is to read it and most importantly, it works.

Nice.
Though a little late for me.
I did it the oldfashioned way: by scrolling through my games shelf, entering all the games in LibreOffice Calc by hand, and then sorting them alphabetically.

But if I ever have to do it anew - I'll use your tip.
Thank you. :)