User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36 Steps to reproduce: have a long line of Japanese text with plenty of Japanese commas. Set CSS to have word-break: break-all and width to be less than the text. (e.g. https://jsfiddle.net/y3x015dv/1/) ///html////// <div class="long-text"> [メンバー登録] をクリックすることにより、ラララの利用規約、プライバシーポリシー、Cookieポリシーに同意したものとみなされます。 </div> ////CSS//// .long-text { word-break: keep-all; width: 400px; } Actual results: the text broke on the square bracket, but not on any of the commas so the text over-flowed in one super big line. Expected results: the text should have broken on the commas. (see the js fiddle in chrome)

*** word-break: keep-all ***

also, the text doesn't break on a Japanese parenthesis as expected: (e.g. <p>パスワード（６文字以外）</p> Notice that the parentheses character looks like it is next to a space, however, the space is "baked into" the character.