This version pairs with Pin-op 0.4.2 for Visual Studio Code. The Rules fixes
below live in the IDE half, so update both halves:
https://marketplace.visualstudio.com/items?itemName=conus-vision.pin-op

Rules links a rule back to its SCSS again. The browser names a matched rule by
its index in the CSSOM, and that index cannot be recovered from the stylesheet
on disk: an engine drops every rule whose selector it does not implement, and
from the first dropped rule onwards every later index names a different rule.
Pin-op read that disagreement as "this rule is not identified", stopped before
the source map and showed the generated CSS. Measured on a real theme, one rule
resolved to its SCSS before this fix; 927 do now.

Rules also follows the source map for a rule whose selector the mixin around it
wrote. "@include link-states(hover) { b { ... } }" compiles to ".btn:hover b",
which nesting expansion cannot produce from "b", so the comparison used to
reject the very rule the map points at.

A rule the browser cannot be matched to exactly one rule in the file is still
left unresolved.

In the add-on itself, the Rules pane now says "No element selected" instead of
emptying without a word - the state a selection lost to page script lands in.