You are likely zoomed out on your browser... depends on the browser you are using but you can likely fix this by using the "View" menu at the top of the browser and select 'actual size', '100%', or whatever. If you tell me what browser your using, I could give more specific directions.
I feel dumb , It was the browser indeed but I don't understand how it happened since I didn't change it and how it's changed only in Bitcointalk ? I thought it changes the browser settings and not the web settings . Either way , thanks mate
I got it right when I read the smaller.. smaller part.
Happened to me too a couple of months ago. Was zoomed out to 90% somehow and suddenly was on a different looking forum. Took me a good few minutes to figure out.