website/docs: prepare 2021.12.3 release notes

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

website/docs/releases/v2021.12.md

@@ -177,6 +177,28 @@ This release does not have any headline features, and mostly fixes bugs.
 - web/admin: fix background colour for application sidebar
 - web/elements: fix border between search buttons
 
+## Fixed in 2021.12.3
+
+- *: revert to using GHCR directly
+- core: fix error when getting launch URL for application with non-existent Provider
+- internal: fix sentry sample rate not applying to proxy
+- internal: rework global logging settings, embedded outpost no longer overwrites core
+- outpost: re-run globalSetup when updating config, allowing for live log level changes
+- outposts: handle/ignore http Abort handler
+- outposts/ldap: fix log formatter and level not being set correctly
+- outposts/proxy: add initial redirect-loop prevention
+- outposts/proxy: fix allowlist for forward_auth and traefik
+- outposts/proxy: fix ping URI not being routed
+- outposts/proxy: fix session not expiring correctly due to miscalculation
+- root: allow trace log level to work for core/embedded
+- root: don't set secure cross opener policy
+- root: drop redis cache sentry errors
+- root: fix inconsistent URL quoting of redis URLs
+- web/admin: add outpost type to list
+- web/admin: auto set the embedded outpost's authentik_host on first view
+- web/admin: don't auto-select certificate for LDAP source verification
+- web/admin: fix border for outpost health status
+
 ## Upgrading
 
 This release does not introduce any new requirements.