And which government ID will be followed?

I have 3 first names (like used to be common in Belgium). On my drivers license all 3 names are written in full. My national ID card just mentiones my first & second name in full and my 3th name is an initial. While my current international passport states only my first name in full and my 2nd and 3th name as an initial...

Last I've seen is that new international passports will have all first names again written in full...

But in the end there is still no constistency in the different official document

All my tickets are still only with my first name only, not my 2nd nor my 3th and as long as it works like this I don't add my other names to avaid troubles