Javascript Hacks for Blackboard (a.k.a JS Hacks) is a building block which allows for the injection of arbitrary HTML/Javascript into many pages in Blackboard, providing a platform to modify Blackboard in ways not easily possible before.
See the Wiki for more information, or to download some prebuilt packages.
JS Hack uses SLF4J/Logback for logging. Libraries utilised by the tool which use Log4J have the logs piped into SLF4J using log4j-over-slf4j. This means that it is not vulnerable to any Log4J vulnerabilities.