diff --git a/Available-C#-and-.NET-features.md b/Available-C#-and-.NET-features.md
index ac6c75a..6976828 100644
--- a/Available-C#-and-.NET-features.md
+++ b/Available-C#-and-.NET-features.md
@@ -18,6 +18,7 @@ The official BCL type reference now has a ["`netstandard2.0` w/ polyfills" filte
 I have not considered Framework 4.7.2 and below as there is little reason not to upgrade to Framework 4.8.
 I have not considered Framework 4.8.1 because it matches Framework 4.8 in terms of language features and is generally not useful.
 I use Standard 2.0 and not Standard 2.1 as the latter is not subsumed by Framework 4.8, rendering it useless.
+Presumably Mono and the Windows implementation are the same when it comes to these runtime-support-gated features, but for reference, all testing was done with Mono.
 
 > Note: .NET calls destructuring "deconstructing", not to be confused with destructing which .NET calls "finalising".