I tried to include highlighted fragments into HTML email but highlighting tags were lost somewhere
In ctx.payload.hits.hits[].text there is text correctly highlighted by <em> tags but finally in e-mail body these tags disappeared.
Body is rendered by "body.html" xmustache template using following code inside
{{#ctx.payload.hits.hits}}
{{#highlight.text}}<p>{{{.}}}</p>{{/highlight.text}}
{{/ctx.payload.hits.hits}}
Somewhere on the way from payload to email body <em> tags disappears.