LinuxServer Changes:
Rebase to Alpine 3.14.
bookstack Changes:
Security Release
BookStack v21.11.3 has been released.
This is a security release that helps prevent potential discovery and harvesting of user details including name and email address.
It's advised to upgrade as soon as possible if your BookStack instance is public or is used by untrusted members.
Thanks to @Haxatron for discovering and reporting this vulnerability via huntr.dev.