[css-ui-4] Turn issue into note, since we resolved on it

Author: frivoal

css-ui-4/Overview.bs

@@ -550,10 +550,10 @@ Omitted values are set to their initial values.
 		The UA must allow selections to extend across this element,
 		and such selections must include the content of the element.
 
-		Issue: At the time of writing, browsers behave differently from eachother
-		about selections started outside and selections going across the element.
+		Note: At the time of writing, experimental implementations behave differently from eachother
+		about selections started outside and selections going into the element.
 		The behavior can be observed even on browsers that do not explicitly support ''element''
-		by trying to select into / across a <{textarea}> or a contenteditable element.
+		by trying to select into a <{textarea}> or a contenteditable element.
 
 		Issue: Not sure the name ''user-select:element'' is particularly clear
 		about what this means.