my question is about vertical scrollbar only in opera

in opera there is a huge vertical scrollbar that is being created by the browser and this happens only in opera no other browser

i noticed when i scroll a few times in opera when the huge scrollbar is not present and later a huge vertical scrollbar appears and sometimes by default when i click on a page this huge vertical scrollbar appears

how to avoid this unwanted huge vertical scrollbar in opera i am using opera 9

An example page and screenshot would probably help.

Without seeing the site, it is hard to know what to debug. But, I do remember reading something similar before. The solution was putting overflow:hidden on the main wrapping div.