Misplaced hyphen and period appearing at the end of comments

Question

There seems to a small issue with rendering latex maths formulas in the comments area. When entering a formula that spans more than one line, a '. -' appears after the first line. It clearly should not be there, rather it should be further down just before the author name. See this post for an example:

Proof that a $\sigma$-field contains the sets $A \cap B$, $A \setminus B$, and $A \triangle B$.

Screenshot (Google Chrome):

Answer 1

If in your comment, your meant this comment, here's what I see (Firefox 13):

In particular I don't see any spurious hyphens.

There is an extra period at the end of the first line. But that is because you typed a period after the extra long equation. It may be slightly misplaced, but certainly not spurious.

To put the period at the correct place, you should really not use the in-line math environment $...$ for such long expressions, and instead use the displayed math environment $$...$$. In my two comments below I showed what it would look like if you used the double dollar sign instead of the single. The first comment puts the trailing period outside the Math environment, so it now appears right in front of the signature line. And the second comment puts the trailing period inside the math environment, so now it appears at the end of the math expression.

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Edit in response to comment: There is a trailing period. This is what you typed:

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Edit in response to other comment: Okay, on Chrome there's a period and a hyphen. Again, they may be misplaced, but they are not spurious. But the solution I gave above (and the comments shown below) works for both firefox and chrome.

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Let me cook up the expression a little bit to show more clearly what MathJax is doing. By rewriting your expression somewhat I can force MathJax to break the line only at certain spots. And now you see that if I write ${x\in A \triangle B \iff x \in [(A \cup B) \setminus (A \cap B)]} \iff {x \in [(A \setminus B) \cup (B \setminus A)] \iff x \in (A \setminus B) \cup x \in (B \setminus A)} \iff {(x \in A \land x \notin B) \cup (x \in B \land x \notin A) \iff (x \in A \land x \in B^c) \cup (x \in B \land x \in A^c)} \iff {x \in (A \cap B^c) \cup x \in (B \cap A^c) \iff x \in [(A \cap B^c) \cup (B \cap A^c)]} \iff {x \in [(A^c \cup B)^c \cup (B^c \cup A)^c)] \in \mathcal{F}}$, it renders like this because the entire in-line math expression is treated as one unit to be stuffed into the line.