Discard tabs in the background

lib/TabManager.jsx

@@ -654,18 +654,12 @@ class TabManager extends React.Component {
 		browser.tabs.remove(tabId);
 	}
 	async discardTabs() {
+		var _this2 = this;
 		var tabs = Object.keys(this.state.selection).map(function(id) {
-			return parseInt(id);
+			return _this2.state.tabsbyid[id];
 		});
 		if (tabs.length) {
-			for (var i = 0; i < tabs.length; i++) {
-					if(!this.state.tabsbyid[tabs[i]].discarded) {
-					browser.tabs.discard(tabs[i]).catch(function(e) {
-						console.error(e);
-						console.log(e.message);
-					});
-				}
-			}
+			browser.runtime.sendMessage({command: "discard_tabs", tabs: tabs});
 		}
 		this.clearSelection();
 	}

lib/background.js

@@ -15,6 +15,17 @@ browser.runtime.onStartup.addListener(
 	}
 );
 
+async function discardTabs(tabs) {
+	for (var i = 0; i < tabs.length; i++) {
+		if (!tabs[i].discarded) {
+			browser.tabs.discard(tabs[i].id).catch(function (e) {
+				console.error(e);
+				console.log(e.message);
+			});
+		}
+	}
+}
+
 async function moveTabsToWindow(windowId, tabs) {
 	for (var i = 0; i < tabs.length; i++) {
 		var t = tabs[i];
@@ -723,6 +734,9 @@ browser.runtime.onMessage.addListener(function(request, sender, sendResponse) {
 		case "update_tab_count":
 			updateTabCount();
 			break;
+		case "discard_tabs":
+			discardTabs(request.tabs);
+			break;
 		case "move_tabs_to_window":
 			moveTabsToWindow(request.window_id, request.tabs);
 			break;