On other platforms? Used to be often... I still change it often on Discord but Tumblr, Facebook, and Twitter have all been the same for a while -- I found stuff that works for me on those platforms, I guess.
On other sites, like forums (including this one) I select from my folder of avatars and probably change it often until I find one that feels right for the context. In this case, I think the only thing that's really right for the context is art of my sona, which I'm waiting on... so I'll change it then.