A short video showing some tricks of the game developers to fix the “jambs” of the game client. Such tricks are not uncommon for them.
In this case, there is some deviation from the rule called “interaction distance”. If for some reason the character cannot come closer to the NPC, but he sees him, then the dialogue begins without any problems.
Such behavior is nonsense for Java servers, because the “fathers of L2J” did not assume that the developers from NC Soft would resort to such tricks.
And in general, it would be stupid to perceive the game of the early 2000s as something perfect, because it is worth paying tribute to the developers who found many ways to bypass the technical limitations at that time and give players such a wonderful gameplay.