How can we hide the parent’s theme url at the child themes details on a multisite?

I finally managed to work it out myself, after reading a similar question over at the Stackoverflow Site:

div.themedetaildiv > p:nth-child(n+3) { display:none; }

Which means: we go to the theme details and hide all paragraphs after the second one. The first one being the version number of the theme (Version: 1.4.2).

Hope it helps someone else.