Open a terminal/command prompt and run:

java -jar jtube.jar --version

or

java -jar jtube.jar --help

Look for a build date or version number (e.g., 2025.03.15).


If the developer provides source code:

git clone https://github.com/username/jtube.git
cd jtube
mvn clean package   # or gradle build

The updated JAR will be in the target/ folder.

If you have just updated the JTube Jar and it is not working, here are the most common fixes: