how can i style annotator findings : Intellij Plugin Development

Hi,

For an intellij plugin project,

I am using an externalannotator instance in order to detect and report findings for an xml tag for an xml document.

It works great and shows up findings in a pop up on mouse over. However i am not able to style the messages the way i would like to.

Would appreciate tips on how to achieve that. I have tried sending an html text, but it shows up the html tags in the pop up.

Codebase is :

findingList.forEach{it->run {
    var message = StringBuffer()
    message.append(it.name)
    message.append(" : ")
    message.append(it.description)
    holder
        .newAnnotation(warning,message.toString())
        .range(textRange)
        .create()
}}

It looks like so:

Versions used:

id("org.jetbrains.kotlin.jvm") version "1.7.10"
id("org.jetbrains.intellij") version "1.12.0"