I’m surprised that this one hadn’t been mentioned already: the analogue home video versions (BETA, VHS, LD, CED, VHD) of Back to the Future, featured the closing card below that confirmed plans for sequels.
The “Special Longer Version” of Star Trek: TMP as seen on TV, VHS, BETA, VHD and LD, has never been (officially) released on digital home video. It differs from both the Director’s Edition and the theatrical version.