I just tested both on the text "Look Dick. See Jane. Jane run home. I says you go home to. They eats dinner." LanguageTool does what I would expect. Harper does not. However, both whine about two spaces after a period.

Edit: Alas, Hacker News also removes the extra space after periods.

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dreamcompiler 16 hours ago | parent | next [-]

Extra space after periods is never correct with proportionally-spaced fonts, which is why all browsers remove it by default.

Two spaces after periods is a kludge invented for typewriters that had monospaced fonts and touch typing teachers need to stop teaching it in the modern era where most writing uses proportional fonts.

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dkga 16 hours ago | parent [-]

Curiously, it‘s also a tell-tale sign that a North-American typed the text.

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FabHK 16 hours ago | parent [-]

Just as a space before colons or exclamation marks is a sign that someone francophone typed it.

	▲	dkga 15 hours ago \| parent [-]
		Indeed - especially the space before colons and semi-colons. The space before exclamation marks sometimes happens in informal typing amongst Brazilians. But never the space before colons/semi-colons.

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codesnik 17 hours ago | parent | prev | next [-]

browser rendering does. You'd need white-space: pre-wrap rule to retain double spaces.

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chilipepperhott 11 hours ago | parent | prev | next [-]

Harper will detect those errors in its next release.

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14 hours ago | parent | prev [-]

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