Updated 1.3 Implementation (markdown)

1.3-Implementation.md

@@ -38,6 +38,7 @@ Also:
    * `[SETUP-CHROME]` changes how Firefox itself behaves (i.e. NOT directly website related)
    * `[SETUP-PERF]` may impact performance
 - :star: The following all have documented privacy concerns and Proof of Concepts, but the threat from these are likely to be low for most users, so feel free to change them. Leaving them as is does not break anything (yet), but might give you enough of a performance gain to make the trade-off worthwhile.
+   * IPv6 (0701) we only disable this as a fallback, read 0701
    * HTTP2 (0702)
    * AltSvc (0703)
    * Cache (1001) Note that we clear cache on close (2800s)