Install eclipse-wtp-xsl by entering the following commands in the terminal:
sudo apt update sudo apt install eclipse-wtp-xsl
Eclipse Extensible Stylesheet Language tools
The Eclipse Web Tools Platform (WTP) project extends the Eclipse platform with tools for developing Web and Java EE applications. It includes source and graphical editors for a variety of languages, wizards and built-in applications to simplify development, and tools and APIs to support deploying, running, and testing apps. . This package contains tools Extensible Stylesheet Language (XSL) and allows one to run and debug XSL transformations.