Talking to people

I'm getting better at chatting to strangers on the train, provided they want to talk about the Riemann Hypothesis and guaranteed basic income.

But I still want to get better at finding topics of conversation intermediate between "nice weather, isn't it?" and "so, lets argue about politics and god, and lets talk about set theory". Any suggestions for finding interesting but not-too-contovertial topics, if I'm talking to friends or acquaintances and don't want to force them to carry the conversation?

Enter without autocomplete

If "enter" is the shortcut key for "autocomplete", what is the shortcut key for "the thing I have typed, submit it"?

I've had this problem in facebook, and in spreadsheets, and sometimes with autocomplete on my phone. It seems they're trying to be too helpful, but I don't know if I'm using a bad version, or if my instincts are wrong, or if they literally have removed the ability to enter original text.