Hi conformal_gk,
this is not good, however I am not impacted by such issues. For me the answer box including the preview works as usual (using Firefox and Windows Explorer).
If the issue still persists, you could write a bug report here
https://www.physicsoverflow.org/questions/meta/bug
including Information which browswers you are using from what devices (mobile or Desktop).
However, Polarkernel is out of office today and will be able to do something about it not before tomorrow.
Best wishes and thanks for the nice answer here ;-)
https://www.physicsoverflow.org/38833/do-all-mathcal-2%24-gauge-theories-descend-from-string-theory?show=38835#a38835