It's not mods. I removed all my mods, reloaded a save before the dialogue to enter the Inn, and the combat begins immediately after dialogue.
I don't think it's always as simple as removing all mods. Things can still be left behind which impact the game.
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Anyway, as I have a completely vanilla game that has never had any mods, it's not happening to me. My question is, if it's not mods, why isn't it happening in my game? I'm not asking to "checkmate" an argument. It's a legitimate question. I sincerely believe this is a mod issue, and I accept that I may be wrong.