"False memories can sometimes be shared by multiple people." Rational explanation.
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My explanation:
Our entire consciousness is jumping between parallel universes so often that this effect takes place.
The Mandela effect I could confirm affirmative is the movie "Interview with the vampire" in this universe, in the other universe is "Interview with a vampire", both universes have google search, in one universe almost all the movies will say Interview with a vampire, in this universe almost all the movies will say Interview with the vampire, for that reason someone could remember the name of the movie "Interview with a vampire". The location of earth on Milky way was different on both universes.
When you jump from one universe to a different one don't feel sad, because you are living in both universes, the differences between universes are minimal, everything is interconnected.
There are glitches, one way to detect jumps is looking carefully when everything goes slow motion for a few seconds (15 or less), including cars on movement. Time changes.
Regards