Just for the record?
Opera 10.6 seems to be very old...
Interestingly, we have a css hack that's supposed to fix it, if only it wasn't invalid css (nested properties).
https://github.com/wikimedia/portals/blob/8673983fbc5855fdd59caf92792a9d39b63bf077/dev/wikipedia.org/assets/postcss/_search-language-picker.css#L169-L176
From http://www.opera.com/docs/specs/presto2.12/css/o-vendor/
-o-prefocus
-o-prefocus is a pseudo-class introduced in Opera 9.5 that allows styles to be targeted for Opera only.