Filter does not appear when adding a text format

Hello,

I just installed the php module (means I downloaded the .tar file, then installed it from the extend interface; I don't think the mistake comes from this ..) but when I am trying to add a new text format, there is no filter related to php that appears in the 'enabled filters' checkboxes (only the core filters).
I am currently using Drupal 8.7.5.
Am I missing something about the installation of the module ?
Is there maybe a manual way to fix this ?

Thanks.