Where would you want to create a save button?
If you look on: https://ek2021.kampautolease.nl/voorspelling-achtste/
I don’t want a button under the match but only one button on the bottom of the page.
I can’t see that page without being a player in the pool.
You can only hide the buttons if they are all in the same HTML form. Then it’s a matter of selecting the correct button with CSS and setting the display property to none.
If you used shortcodes to build the page, then it’s not possible to hide the buttons, because every button will only submit the form that it belongs to.
