Users can use 'cabal init' to bootstrap projects. 'cabal init -i' does not automatically fill in author name and e-mail anymore. The solution is to add a guess (=default) to the prompt.
[
  {
    "endline": 359,
    "file": "cabal-install/src/Distribution/Client/Init/Interactive/Command.hs",
    "function": "authorPrompt",
    "module": "Distribution.Client.Init.Interactive.Command",
    "startline": 358
  },
  {
    "endline": 363,
    "file": "cabal-install/src/Distribution/Client/Init/Interactive/Command.hs",
    "function": "emailPrompt",
    "module": "Distribution.Client.Init.Interactive.Command",
    "startline": 362
  }
][
  {
    "endline": 361,
    "file": "cabal-install/src/Distribution/Client/Init/Interactive/Command.hs",
    "function": "authorPrompt",
    "module": "Distribution.Client.Init.Interactive.Command",
    "startline": 359
  },
  {
    "endline": 366,
    "file": "cabal-install/src/Distribution/Client/Init/Interactive/Command.hs",
    "function": "emailPrompt",
    "module": "Distribution.Client.Init.Interactive.Command",
    "startline": 364
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]