Oh interesting. Running strings on some relevant JAWS binaries, I do see "line-number". So apparently they do use it for something, though I don't know whether they care, since Chromium doesn't implement it.
Bug 2007033 Comment 2 Edit History
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Oh interesting. Running strings on some relevant JAWS binaries (specifically FSDomNodeIAText.dll), I do see "line-number". So apparently they do use it for something, though I don't know whether they care, since Chromium doesn't implement it.