Constant PREFIX 

pub const PREFIX: &str = "gh3|";

What every token this plugin gives starts with, so a reader can tell it from another plugin’s.

gh3 since the item’s facets — its own kind, its board field values and its labels — joined the token. A gh2 token, which lacked them, could stay equal across a label renamed or recoloured and a field option renamed, and order a token read after a far end’s deletion before the one held; a gh1 token lacked the relationship count and the repository too. Neither is a token this plugin orders or ever gives, so an entry or a copy that recorded one reads its item again once rather than trusting a version that could not see those.