JavaScript "Hide/Show" problem on Opera

Yey, my first post on this forum and i hope its the right thread... Or does this belong to Javascript thread...oh well, moderators, do your duty (and sorry)

But to the point:
While ago after updated Opera browser to newest version i have had this one problem. For first i thought it was the CAPTCHA that was troubling me, because when i tried to download file from online file sharing site where some uses CAPTCHA, it didnt show at all (other browsers didnt have this problem). But after taking some time to search the problem i opened Operas javascript error console and saw that it was some sort of "Hide/Show" command error from javascript. After testing other sites who uses this command to hide certain content from audience i knew it was javascipt error.

After the update i didnt change any settings that might have tempered javascript nor did i disable it anytime from any site. I even tried to reinstall browser (keeping my user settings) but nothing. For file downloads i have to use firefox for Hide/Show JS command to reveal CAPTCHA etc.

I hate to copy the links for other browsers to download anything because something in Opera is denying this from me.
Or is it just me that doesnt quite get things to work out

Could you kindly provide a link? I can't remember having any troubles with captchas as long as js was enabled, but that doesn't mean anything...