docs: Mention deprecated features

Author: igorlukanin

docs/pages/product/distribution.mdx

@@ -54,6 +54,13 @@ that breaking changes can happen both in _major_ and _minor_ versions. Before
 upgrading, it is recommended that you check the [release notes][link-releases]
 on GitHub and read [changelog entries][link-changelog] in the blog.
 
+<WarningBox>
+
+You can find a list of currently [deprecated features][link-github-deprecation] on GitHub.
+Usually, there are also deprecation notices in the documentation that look similar to this one.
+
+</WarningBox>
+
 Additionally, Cube Cloud provides [update channels][ref-update-channels] where
 versions are marked as either <Btn>Stable</Btn> or <Btn>Latest</Btn>.
 
@@ -92,6 +99,7 @@ List of LTS releases:
 [link-dockerhub-cubestore]: https://hub.docker.com/r/cubejs/cubestore/tags
 [link-apple-silicon]: https://support.apple.com/en-us/116943
 [link-semver]: https://semver.org
+[link-github-deprecation]: https://github.com/cube-js/cube/blob/master/DEPRECATION.md
 [ref-infrastructure]: /product/deployment/cloud
 [ref-workspace]: /product/workspace
 [ref-deployment]: /product/deployment