fast-sell-steam.user.js

// ==UserScript==
// @name Steam — fast sell
// @include  http*://steamcommunity.com/profiles/*/inventory*
// @include  http*://steamcommunity.com/id/*/inventory*
// @description Fast sell Steam items with current price plus extra (epsimatic's mod)
// @version 0.14
// @namespace https://greasyfork.org/users/6507
// ==/UserScript==

const sell_price_factor = 1.4; // Add 40%!

(function (window, undefined) {  
    var w;
    if (typeof unsafeWindow != undefined) {
        w = unsafeWindow
    } else {
        w = window;
    }
    if (w.self != w.top) {
        return;
    }

	jQuery(document).ready(function($) { 
//		$('.item_desc_content').append('<a style="background: linear-gradient(to bottom, rgba(33,101,138,1) 5%,rgba(23,67,92,1) 95%)"class="item_market_action_button_contents item_market_action_button fs" href="#">FAST SELL</a>');
//<a class="item_market_action_button item_market_action_button_green"><span class="item_market_action_button_edge item_market_action_button_left"></span><span class="item_market_action_button_contents">Продать за 7.70</span><span class="item_market_action_button_edge item_market_action_button_right"></span></a>
	  $('.inventory_iteminfo').append('<a class="fs item_market_action_button item_market_action_button_green"><span class="item_market_action_button_edge item_market_action_button_left"></span><span class="item_market_action_button_contents">Быстро продать</span><span class="item_market_action_button_edge item_market_action_button_right"></span></a>');
		$('.fs').on('click', sellOne);
	});
})(window);

		
function sellOne() {

	inf = jQuery('div.inventory_iteminfo:visible').find('.item_market_actions').text();	

	expr = /(\d+(?:\.|,?)\d+)/;
	price = expr.exec(inf);
	price = price[1];

	price = parseFloat(price) * sell_price_factor;

	SellCurrentSelection();
	document.getElementById('market_sell_buyercurrency_input').value = price;
	SellItemDialog.OnBuyerPriceInputKeyUp();
	document.getElementById("market_sell_dialog_accept_ssa").checked = true;
	document.getElementById("market_sell_dialog_accept").click();

	document.getElementById("market_sell_dialog_ok").click();
}