This doesn't look right.
should give the same result. They don't.
I'll debug this further. Please don't use workarounds like \! because things will look weird after an update. (Hmm, StackExchange hasn't updated MathJax for 3 years.)
Based on your questions you seem to have a misconception as to the purpose of closing a question. Please read What does it mean if a question is "closed"? first, then come back to this.
Why would I close my own question?
I imagine this is a rare scenario, but it is sometimes used, e.g. when the asker finds a duplicate of their own question after ...
According to this post on MetaSE, the issue has been discovered and a solution is enroute. From Marc Gravell, an SE staff member,
Sorry about that. What happened here: the favorites/ignored feature is implemented client-side; a UI tweak changed the DOM in a way that broke the jQuery selector, meaning that it no longer found the tag data. I've put a PR ...