Badge color not working inside active Tab title

[arrancardnell]

Version & browser

uiv 0.31.2
Firefox 65.0.2 (64-bit)

Which component

Tab

Steps to reproduce the problem

Using a Tab with html-title and a backstring HTML string as follows:

    <Tab
      html-title
      :title="`<i class='fa fa-fw fa-filter'></i> Filters <span class='badge'>0</span>`"
    >

Expected behavior

Badge inside an active tab should have a white background with tab color text as detailed in the docs here

Actual behavior

Badge still has grey background even with active tab.

This seems to be because the content of the tab link is wrapped in a span element. Moving the contents out of the span fixes the issue.