Extensions were introduced in 11 version almost two years ago.

Now Opera is ditching widgets and unite to focus on extenions.

This is a pity. I have a really nice and unobtrusive SVG Opera clock widget in the corner of my screen, which starts and runs completely separately from Opera. I understand that this is not possible anymore with extensions. I really hope I can keep it after upgrading.

I just read that on their main page. Are they getting a lot of support from developpers for extensions ?

Pretty much. What do you need?