Opera always used to be this way on the desktop and just hang on Linux at least when it ran out of resources (maybe Windows too though dont use Windows anymore except a little bit at work where Opera isn't installed); I haven't noticed it as much since 10 and 11 on the desktop.

I've not had it hang on me since 10.something, but I do have a lot more RAM nowadays (since 10.something also, but not necessarily same version as I stopped noticing it on).