There are definitely some problems with the interface at the moment. I think the powers that be did a major site upgrade last week and this has changed the way things work.

The context menu (right-click) seems to have been disabled in the box. This means that you have to use CTRL-V to paste. If you type in Word and directly paste into the box, this seems to work okay, but C&P from a saved Word document seems to copy in formatting stuff from Word too.

You can use the "paste from word" box in the menu but you must do this before clicking in the box. Once you click in the box, you have to refresh the entire page to get it back!

If you're writing long, complex posts, make sure to save elsewhere before submitting to the site. This is good practice anyway.

The site-changes may affect some browsers more than others. I usually use Firefox which works as described above, but others might perform better or worse. If you use script-blockers of any kind (e.g. NoScript) make sure the site is whitelisted or disable them when visiting here.

Cleaning your browser history can sometimes help with issues of this sort as well.