TooltipAppender

The registration point for item tooltips, a NeoForge extension point. Each module registers its own appender, so the resource, currency, quality and aura storage displays stay uncoupled - adding one tooltip line does not touch anybody else's.

Two shapes, both on RegisterTooltipAppendersEvent:

Shape	Where it is used
event.registerAppender(TooltipLocation.HEAD / POST_CUSTOM, ...)	A section at a position: quality goes at HEAD, while aura storage, artifact bindings, currency value and the talisman hint follow the custom contents.
event.registerComponentAppenderBeforeAll(component, TooltipAppender.createComponentAppender(component))	A whole section driven by an item component: the bell, the spirit beast bag, a formation plate or a storage container each register one, because the thing itself carries its own explanation.

Appenders at one location run in registration order (the order their event handlers are called in), so a block of lines that has to read in a fixed order can only come from a single appender - split across two, it cannot be ordered. A talisman carrier is the case: its inscriptions, charge and gesture hint are all written in order by TalismanTooltipAppender, and the aura storage line steps aside for a carrier; the quality line still comes from the quality module at HEAD, on top.

The rule is one appender per module: what the lines say and in which order belongs in that module's own class. How a number is spelled (at most two decimals, a sign on gains, and a translated separator between the parts of a line rather than a hard-coded punctuation mark) goes through TooltipText, see Public API.