In the settings there is the heading "CLIPS".
The entry "Free Preview Push" can be set to "NEVER", then no new previews will be loaded automatically.
Only the previews that can be seen in the Preview tab are shown.
If you want to deactivate the preview of a show, click on the tick symbol. (Previews tab)
If this show is bought later, this show is still deactivated and will not be played automatically. This show can then be activated again by the tick symbol.
###
There is no way to deactivate all shows of a series (Fxxxx) with a few clicks. Each show must be deactivated individually.