Cloze Deletion Immediately after \begin{aligned} in Equation Not Shown on Card

When a MathJax equation contains an `aligned` environment, if the first non-whitespace within the environment is a cloze deletion, then the deletion is not shown correctly. In the following example, the MathJax preview should show "[0]" on the first line, before the comma.


This isn't a problem only with the MathJax preview. The card does not show "[...]" on the first line either.

Here is the code for the example note:
```
\[\left\{\begin{aligned}
{{c1::0}}, \\
{{c1::1}},
\end{aligned}\right.\]
```

I'm currently using Anki 2.1.55 Beta, but I've observed this problem on several previous versions of Anki.