Bug introduced in 10.0.0 and fixed in 10.0.2
Recently I installed Mathematica 10 on Windows 8 x64 machine. Before that I had a prerelease version of Mathematica 10 installed on my laptop. I observed very annoying bugs in the FrontEnd on both machines: at some random moment during editing a notebook, some keybord shortcuts (e.g.
Ctrl+S etc) start doing things completely different from they are supposed to do: change the notebook stylesheet, open new windows, comment out the selected text etc. The menu items corresponding to those shortcuts do the same crazy things. To save the current notebook I have to invoke
NotebookSave function because there is no way do it using graphical interface. Restarting Mathematica solves the problem for a while, but soon it reappears. Does anybody else observe this behavior?
Update: It looks like this bug was fixed in version 10.0.2. Many thanks to the developers!