@TugrulTemel In general when I have website issues, I find it useful to right-click anywhere on it and select "inspect element" to open developer tools. Then I choose the "console" tab and see any error being generated. Sometimes this gives a hint of what the issue is. Other times I have to deactivate the ad blocker or just try with a different browser.

@gdelfino Dear @gdelfino, Thanks for your information. I tried Fireworks as a browser and everything returned to normal. However, I really want to solve the problem for Safari (MAC) because it is my main browser. I will try you suggestion but I do not know what you mean with "right-click anywhere on it". When I click on "Review my question" button on MSE, nothing happens. No sign of anything...Can you tell me precisely where to use right-click? Thanks.