With the following raw html.
<div><div><anki-mathjax></anki-mathjax><blockquote>a</blockquote></div></div>
Place your cursor to the right of the letter “a” (in the WYSIWYG). Then hit backspace.
The html will become
<anki-mathjax><img src="data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20id%3D%22mdi-math-integral-box%22%20viewBox%3D%220%200%2024%2024%22%3E%3Cstyle%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1999%2Fxhtml%22%3Esvg%20%7B%20color%3A%20black%3B%20fill%3A%20black%3B%20font-size%3A%2020px%3B%20%7D%3B%3C%2Fstyle%3E%3Cpath%20d%3D%22M19%203H5C3.9%203%203%203.9%203%205V19C3%2020.1%203.9%2021%205%2021H19C20.1%2021%2021%2020.1%2021%2019V5C21%203.9%2020.1%203%2019%203M15.9%206.9C15.9%206.9%2015.2%206.6%2014.9%206.6C14.3%206.5%2013.9%206.7%2013.7%207.7L12%2016.8C11.8%2017.6%2011.5%2018.2%2011%2018.6C10.6%2018.9%2010.2%2019%209.7%2019C8.9%2019%207.7%2018.5%207.7%2018.5L8.2%2017.1C8.2%2017.1%209%2017.4%209.2%2017.4C9.5%2017.5%209.7%2017.4%209.9%2017.3C10.1%2017.2%2010.2%2016.9%2010.3%2016.6L11.9%207.4C12%206.6%2012.4%206%2012.9%205.5C13.5%205.1%2014.2%205%2015%205.1C15.7%205.2%2016.5%205.6%2016.5%205.6L15.9%206.9Z%22%2F%3E%3C%2Fsvg%3E" class="mathjax svelte-npojru empty" alt="Mathjax" title="MathJax" data-anki="mathjax" data-uuid="bd012e03-a578-40e8-bad5-a7ff077fb20f" style="--vertical-center:5px; --font-size:20px;"></anki-mathjax><blockquote><br></blockquote>
It will look like this:
This is a minimal example. In practice the occurrence of the bug messes up all the mathjax in the note.
The bug does not happen with only 1 non-nested <div>.
Version 24.06.3 (d678e393)
Python 3.9.18 Qt 6.6.2 PyQt 6.6.1