Yahooメールのボディの行間を変えるTampermonkeyスクリプト

YahooMailLineHeight.user.js

// ==UserScript==
// @name         Yahoo Mail Line Hight
// @namespace    https://roundwide.com/
// @version      0.1
// @description  Set the line height of the e-mail body on Yahoo Mail.
// @author       Kazuhiro Fujieda <fujieda@roundwide.com>
// @match        https://*.mail.yahoo.co.jp/*
// @grant        none
// ==/UserScript==

function setLineHeight() {
    var msg = document.getElementsByClassName('msg-body');
    for (var i = 0; i < msg.length; i++) {
        msg[i].style.lineHeight = "18pt";
    }
}

(function() {
    'use strict';
    const target = document.body;
    if (target == null) {
        return;
    }
    const observer = new MutationObserver(setLineHeight);
    const config = { subtree: true, childList: true };
    observer.observe(target, config);
})();

/*
Copyright (c) 2021 Kazuhiro Fujieda <fujieda@roundwide.com>

Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.
*/