String Duplication Glitch/bug

1.20.6 with experiments enabled (also in versions before, but latest matters). Ok so using some trap doors water and 2 strings, making a contraption as in video below duplicates the string infinitely (at very high speed). Minecraft java 1.20.x

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwiTv_WjscGGAxWdVKQEHZfnNJYQtwJ6BAgTEAI&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DmPJRurTfTLM&usg=AOvVaw05P6GH3OdfyFdoCWyiX3O8&opi=89978449