Shopify's uncooperativeness is really holding back development for one of my apps because of such a small part of it. Since Shopify isn't helping, for now, I'm just using the bulk editor and it's bulk select feature by holding Shift and selecting the first and last product. If you have a lot (I'm talking thousands) of products selected and need to edit their sales channels, use the following Tampermonkey userscript on each of the pages:
// ==UserScript==
// @name Adding All Sales Channels
// @namespace http://tampermonkey.net/
// @version 0.1
// @description Make all selected products visible on all selected sales channels. (Shopify)
// @author You
// @match https://[SHOP NAME].myshopify.com/admin/bulk
// @require http://code.jquery.com/jquery-3.3.1.comp.js
// @grant none
// ==/UserScript==
(function() {
'use strict';
$('.next-checkbox').each(this.attr('checked','checked'));
})();
Make sure to keep the script disabled by default and to change "[SHOP NAME]" to the URL bit of your shop name.
It's still extremely annoying, though, and I'd love it if they would add the ability to manage sales channels from the API itself.
