Consider a particle with position \(X\in \reals\) and velocity \(Y \in \reals.\) The following SDE is called the {{c1::<i>Ornstein-Uhlenbeck process</i>}}: \[\left\{\begin{aligned}mdY&=\underbrace{-b Y d t}_{\text {dissipation }}+\underbrace{q d W}_{\text {fluctuation }} \\<br>d X&={{c2::Y dt}}<br>\end{aligned}.\right.<br>\]
When the card is rendered while studying it, there looks like there are four or five blank lines between the text and the equation.
When I opened the card in the card browser, the preview was initially correct, but as soon as I trivially modified the HTML, the extra spaces appeared also appeared in the preview.
In a similar vein, MathJax is not rendering vertical bars correctly when used in conjunction with \left ... \right. For the following code, the second and third lines of the code are not producing vertical bars. Parentheses appear to render OK.
Ok, so this is not specific to the beta, and is caused by multiple calls to MathJax.startup.getComponents(); . Maybe you could avoid it by setting a variable to ensure you only call it once.