A nested instance opened from a .fig or file JSON document is first linked to its
own component; matching it to the outer main's layer then went by that component's
name instead of the layer's, so nested instances of variants (or under a name of
their own) and their layers stayed unlinked, and a second export lost what they
changed. They go by their own name until they mirror a layer.
Instances write what they change from their main as an override addressed by the
main's id (size, name, paints), what follows from that for their layers as derived
data (size, place, outline, colours their variables give), and a scale factor when
they were scaled as a whole; layers of a nested instance swapped for another
component keep their overrides. Variable collections, modes and variables are nodes
on a hidden page; paints, gradient stops, effects, layout grids and layer fields
name the variables bound to them, and frames and pages the modes they set. Shared
styles are nodes there too, linked from the layers that use them. Variable-width
strokes say their reach on each side of the path. The import reads all of it back
(style definitions and unused styles, variable order and scopes, bindings on paint
lists, stops, effects and grids, page modes, text bindings, width profiles).
bflatastic