In case of HTML exporter, template used for XSLT transformation can be configured in arq.xml via property so it is up to user of that extension to come with a custom one. When no such property is defined, default XSLT template bundled in reporter is used - it is also shipped in jar.

However, there is no way how to define different default template for screenshooter / recorder implementators so target user would use template of that implementation and not the core one.