When I visit https://en.m.wikipedia.beta.wmflabs.org/wiki/Special:MobileDiff/388527#movedpara_3_1_rhs
I see the following HTML in the source:
<a class="mw-diff-movedpara-right data-title-tag=" new"="" href="#movedpara_1_1_lhs">▲</a>
Expected:
<a class="mw-diff-movedpara-right new" data-title-tag=" href="#movedpara_1_1_lhs">▲</a>
This is not a problem in the desktop code.
See https://en.wikipedia.beta.wmflabs.org/w/index.php?title=Moving_content&diff=388527