Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window plugin-bugfix-safari-id-destructuring-collision-in-function-expression-7.22.15.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.