Sightly/HTL tries to render valid markup as output.You can use data-sly-test inside the divs, no must to use sly-elements.

Can you compare too with the core components?They run on 6.3https://github.com/Adobe-Marketing-Cloud/aem-core-wcm-components

See attached a screenshot from /system/console/bundles, as you can there is a variety of version-formats.

Make sure to restart once the instance is quiet again.If you do a tail on error.log you will notice it is still busy for a while

template level only..

You can also watch the new core components (available in 6.3) here: https://github.com/Adobe-Marketing-Cloud/aem-core-wcm-componentsThey have HTL + Sling models

This is the article for 6.2: https://helpx.adobe.com/experience-manager/using/slingmodel_62.html

Add the following dependency to your core/pom.xml        <dependency>            <groupId>javax.inject</groupId>            <artifactId>javax.inject</artifactId>            <version>1</version>            <scope>provided</scope>        </dependency>

This is indeed strange, what version of AEM are you on?

Can you first run "mvn clean install" from the command line and report back any errors?