The Opera WebBrowser is a little bit bare bones compared to FireFox and Google Chrome. However, it's a very light browser on resources and accomplishes everything the other options can. Opera Turbo is an extra feature that condenses websites so that they load faster on slower Internet connections. If you're looking for a lighter browser, then Opera might be the perfect thing for you. It doesn't have as many features as the other major browsers, but it won't use tons of your computer's resources during use.
I use Opera sometimes on the pc, (I use Google Chrome more) and I think that they only lack those extensions am I right? Other than that, I think they're ok to use, and it's much faster than Internet Explorer. I wonder why that browser is so slow. And I also use Opera Mini on my phone, it's way faster than the built-in browser.
Opera has extensions, but we're talking about a limited number of them, especially compared to Chrome and even FireFox. Basically, Opera is a great option if you want a bare-bones approach to Web browsing that focuses upon speed. Opera won't run some of the more advanced websites as well as Chrome, though. I just like it for its simplicity, although Google Chrome will outperform it in a number of areas. Opera Mini is pretty comparable to the mobile version of Chrome, though.
There are some extensions for Opera, but most of them are only available for Chrome and Firefox. For mobile browsers I could recommend you the Dolphin browser. It's made by a independent developer, who takes user feedback serious. It's a simple browser, that's highly customizable and if it's lacking some features you can just tell the developer and he will implement it, when he finds time.
I've used virtually all browsers on the net. In terms of speed, I wouldn't say Opera is the fastest or most light-weight browser. I use K-Meleon and it loads web pages twice as fast as any browser. The only problem is it's an outdated browser. Because of that there are web-pages it can't load. When I come across such pages I use slimboat because it's also light and fast. The only problem with slimboat is that there aren't any fancy extensions developed for the browser. Or maybe it's just me who doesn't know about them?
Does it have extensions like Adblock. I don't mind if it's barebones but I can't stand ads. I'm going to try it out if it has anything similar. Chrome and Firefox have been getting sluggish lately.
Because I do Web Development, I have Opera, but I haven't found any major reason to use it for my browsing. It is lightweight, but if you use the add-on One Tab on Chrome, you can keep a listing of your tabs without running them. It is a smart little app that essentially keeps you from killing your CPU.
I've used Opera on my mobile phone and at first, i was impressed by how fast it loads website pages compared to the more popular browsers that I've always wondered what's the catch. As i continue to use it, I've encountered a really major flaw as far as browser goes. More often than not it would display some web pages in a really scattered kind of way. The contents, links and what not are all over the place which of course is such a huge turn off. I guess there's the catch I've been looking for. I stopped using it altogether. I know it might be because some websites doesn't support mobile platform which is why i decided to just settle on Safari. ;(
I use Opera on my PC and it it amazing. It's really fast and very light on the system. I can open multiple tabs still get no stutter (of course it's probably because my RAM is notched so high) But I hate Opera on the phones, most of the time Opera mobile is very clunky and some websites don't even load fast enough.
I use Opera on the PC but not in mobile. I find the mobile version to be, well not good for me at least but back when Symbian was still a thing I love Opera on mobile. But now it's just, well I don't like it anymore but the PC version is really good.
I used to be an Opera fan, but I feel like they have lagged behind Firefox and Chrome so much over the past couple of years. Yes, their extensions are very limited. Not sure now but I suppose they still can't compete against the big brands in terms of sheer number of extensions. But overall, I'd say Opera is a solid browser.
It's always seemed a lot lighter and less feature filled than Chrome or Firefox. What I do like though as you mentioned, is that it's quite light. Another thing I love is Opera Turbo which makes browsing with a limited connection easier than ever, and makes bogged down free wifi actually worth using. All in all it's okay on it's own, but it still pales to the bigger browsers out there.