How to change Spring Boot dependencies default versions? For example Spring Boot 1.4 uses Thymeleaf 2.1 version but recent version of Thymeleaf is 3.0. So how to change version
The documentation describes how to do this.
Judging by the tags on the question, you're using Maven. You should add a property to your application's pom.xml to set the Thymeleaf version:
3.0.1.RELEASE
There's also a sample application that shows how to use Thymeleaf 3.0 with Spring Boot 1.4 that may be of interest.