When Alan's parents arrive, the peephole under the 5 on his front door disappears and reappears between shots.
Alan's dirt-stained jogging pants get cleaner between shots.
When Tommy and Alan are spooning in bed Alan's hand changes position between camera angles.
The plant that Tommy gives to Alan on their first 'date' is a species that only blooms once. When Alan goes to find Tommy in Mexico several years later the plant is still blooming
In the "1977" segment, the beer can has a modern-day pop-top.
In the "1984" section, the song "Oh Sheila", by Ready for the World, is played on the stereo; this song came out in late 1985.
In the park jogging scene set in 1977 Beverly is running in spandex and leggings. Leggings were not popularized and mainstreamed until Flash Dance created the trend in the early 1980s.
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