Add notes on cascadia behavior that may differ from jQuery`s

Author: mna

README.md

@@ -89,7 +89,7 @@ Utility functions that are not in jQuery but are useful in Go are implemented as
 
 The complete [package reference documentation can be found here][doc].
 
-Please note that Cascadia's selectors do not necessarily match all supported selectors of jQuery (Sizzle). See the [cascadia project][cascadia] for details. Invalid selector strings compile to a `Matcher` that fails to match any node. Behaviour of the various functions that take a selector string as argument follows from that fact, e.g. (where `~` is an invalid selector string):
+Please note that Cascadia's selectors do not necessarily match all supported selectors of jQuery (Sizzle). See the [cascadia project][cascadia] for details. Also, the selectors work more like the DOM's `querySelectorAll`, than jQuery's matchers - they have no concept of contextual matching (for some concrete examples of what that means, see [this ticket](https://github.com/andybalholm/cascadia/issues/61)). In practice, it doesn't matter very often but it's something worth mentioning. Invalid selector strings compile to a `Matcher` that fails to match any node. Behaviour of the various functions that take a selector string as argument follows from that fact, e.g. (where `~` is an invalid selector string):
 
 * `Find("~")` returns an empty selection because the selector string doesn't match anything.
 * `Add("~")` returns a new selection that holds the same nodes as the original selection, because it didn't add any node (selector string didn't match anything).

traversal.go

@@ -20,6 +20,12 @@ const (
 // Find gets the descendants of each element in the current set of matched
 // elements, filtered by a selector. It returns a new Selection object
 // containing these matched elements.
+//
+// Note that as for all methods accepting a selector string, the selector is
+// compiled and applied by the cascadia package and inherits its behavior and
+// constraints regarding supported selectors. See the note on cascadia in
+// the goquery documentation here:
+// https://github.com/PuerkitoBio/goquery?tab=readme-ov-file#api
 func (s *Selection) Find(selector string) *Selection {
 	return pushStack(s, findWithMatcher(s.Nodes, compileMatcher(selector)))
 }