Why element NOT permanently hideable?

[Ben Stover]

At first here is a (sample) web page in focus:

http://www.giga.de/extra/gaming-pc/specials/arbeitsspeicher-auslesen-welchen-ram-habe-ich/

I want to get rid of the social community icons pretty much at the top.

Therefore I created a GM script with simple instruction (beside the header):

GM_addStyle (".sharing_container.v1.top.floating { display: none !important; }");

See attached snapshot.

Yes, this hides the five social community buttons.....for about 3 seconds (in newest Firefox under 64bit Win 7).

Then these 5 buttons re-appear.

Why?

I guess there is a delayed re-load/refresh mechanism embedded.

How do I hide them permanently?

Thank you
Ben