Once, in a dream, I was trying to Google something, but the text I was "typing" in the search bar kept changing pretty much at random.

Happens to me too, just instead of googling it is usually me trying to write something down, e.g. someone's phone number, and failing to make the text legible or realising I wrote some nonsense instead of what I tried to write.

Actually, this is one of the techniques for lucid dreaming -- how to realize that you are in a dream. You need a test that will reliably give different results in reality and in dreams. Different things work for different people, but reading and writing is among frequent examples. Other examples: counting, or trying to levitate. (With levitation it is the other way round: it works only in dreams.)

Strange. I just now realized I probably never used a computer in my dream, although I spend most of my days at computer. How is that possible? An ad-hoc explanation is that precisely because my life is so much connected with computers, I don't perceive the computer as "computer", but merely as an extension of myself, as another input/output channel. Most of my dreams are about being with people or walking in the nature; and I actually do a very little of that.