Across the network (I've checked SO, MSO, SSE, and MSE), for questions and answers, I see that the entire toolbar on the post editor is blank; no icons are present.



The post preview also does not render.

My console has this error:

Uncaught ReferenceError: MathJax is not defined

which makes me think https://meta.stackexchange.com/a/326710/200582 may be to blame.

Clearing my browser cache did not help.

Tinkeringbell confirms via chat that it's not just me, and that the image upload outage affects chat as well as the main site: https://chat.meta.stackexchange.com/transcript/message/7661235#7661235

  • 3
    Reverting the build. Apr 12, 2019 at 18:18
  • 3
    Build reverted.
    – user1228
    Apr 12, 2019 at 18:29

2 Answers 2


This is fixed.

Or longer: Reverted, patched, rebuilt.

I did an editor fix for math sites, but foolishly did if (MathJax !== undefined) instead of if (typeof MathJax !== 'undefined').

  • Hello, Brian. Is there any news about iOS-app updates? White page after posting any comment makes me angry everytime. Apr 12, 2019 at 19:33
  • @αλεχολυτ things are still trending towards never. That bug is annoying and makes me feel bad, but there's no budget to develop the app and it's providing too much utility to downright kill it. Apr 12, 2019 at 19:37

It's back! Hurrah!

Screenshot showing all is well again.

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