Prettier 2.3.2
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--parser mdx
--arrow-parens avoid
--trailing-comma none

Input:

- A list item.

1.x Some text below the list that starts with "1.x"

Output:

- A list item.

  1.x Some text below the list that starts with "1.x"

Expected behavior:

The text below the list should not be indented. In addition to being aesthetically unpleasant, the indentation actually changes the meaning of the code, as you can confirm in the MDX Playground:

• Without the indentation, the text starting with "1.x" is a separate paragraph outside of the list.
• With the indentation, the text starting with "1.x" is a paragraph within the list item above it.

AFAICT this bug occurs whenever a line of text after a paragraph starts with a string of the form \d\.\S+.