<!DOCTYPE html> <meta charset="UTF-8"> <title>Line break suppression on whitespaces wrapped but not contained in ruby boxes</title> <link rel="author" title="Xidorn Quan" href="https://www.upsuper.org"> <link rel="author" title="Mozilla" href="https://www.mozilla.org"> <span style="white-space: pre"><rb>a</rb><rb> </rb><rb>b</rb></span>