Thanks @a_5mith, let us know. The tags one definitely sounds like a new bug though.
gh#1947julianlam created this issue in NodeBB/NodeBB closed Topics with tags with an ampersand in it are not found in the tags page #1947
One of the older axioms of SEO is that you should always have the most important text on your page be in an H1 tag and that you should have one and only one H1 tag on the page.
The Persona theme (and others?) can have multiple H1 tags. I think this is due to the markdown properly rendering a header to H1. Is there any possibility I can convince the NodeBB team to have the markdown header1 translate to h2 and so down the line instead of the current methodology?
<div class="h1"> might work, so that styling isn't affected.