tt-rss/plugins/shorten_expanded/init.js

var _shorten_expanded_threshold = 1.5; //window heights

function expandSizeWrapper(id) {
	try {
		const row = $(id);

		console.log(row);

		if (row) {
			const content = row.select(".contentSizeWrapper")[0];
			const link = row.select(".expandPrompt")[0];

			if (content) content.removeClassName("contentSizeWrapper");
			if (link) Element.hide(link);

		}
	} catch (e) {
		exception_error("expandSizeWrapper", e);
	}

	return false;

}

require(['dojo/_base/kernel', 'dojo/ready'], function  (dojo, ready) {

	ready(function() {
		PluginHost.register(PluginHost.HOOK_ARTICLE_RENDERED_CDM, function(row) {
			if (getInitParam('cdm_expanded')) {

				window.setTimeout(function() {
					if (row) {
						const c_inner = row.select(".cdmContentInner")[0];
						const c_inter = row.select(".cdmIntermediate")[0];

						if (c_inner && c_inter &&
							row.offsetHeight >= _shorten_expanded_threshold * window.innerHeight) {

							c_inter.parentNode.removeChild(c_inter);

							c_inner.innerHTML = "<div class='contentSizeWrapper'>" +
								c_inner.innerHTML +
								c_inter.innerHTML + "</div>" +
								"<button class='expandPrompt' onclick='return expandSizeWrapper(\""+row.id+"\")' href='#'>" +
									__("Click to expand article") + "</button>";
						}
					}
				}, 150);
			}

			return true;
		});
	});

});