update API manual link for automatic updates at release time

diff --git a/index.html b/index.html
index a461cb57e3059440b542a498bc135716cb705380..4ae52009acd64a8b55e00b16dd6df141cfa9420d 100644 (file)
--- a/index.html
+++ b/index.html
@@ -170,7 +170,7 @@ At the top, you'll find simple methods, using trivial arguments and behavior.
 Then, at each new paragraph, the API introduces new concepts and parameters,
 giving gradually more control for advanced usages.
 
-You can learn more about Zstandard API by reading [its documentation](http://facebook.github.io/zstd/zstd_manual.html).
+You can learn more about Zstandard API by reading [its documentation](https://raw.githack.com/facebook/zstd/release/doc/zstd_manual.html).
 
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