I’ve thrown together a quick script for Opera that you can use if you’d like to see rounded corners (aka border-radius). It seems that Twitter currently sends Opera a style sheet with empty settings for rounded corners…
…so, all I did was write a script that will insert a link to a style sheet that’s stored here at kyleabaker.com which overwrites these empty styles with the correct ones.
Lastly, save the “Twitter-Rounded” script to your UserJS folder that you setup in the steps above.
Now you have a more pleasant looking Twitter page in Opera 10.5. 😉