Improve handling of target="_blank" links

package.json

@@ -45,6 +45,7 @@
 		}
 	},
 	"dependencies": {
+		"parse-domain": "^7.0.0",
 		"tippy.js": "^6.3.7",
 		"webextension-polyfill": "^0.8.0"
 	},

src/content/click-element.ts

@@ -1,4 +1,5 @@
 import browser from "webextension-polyfill";
+import { parseDomain, ParseResultType, fromUrl } from "parse-domain";
 import { focusesOnclick } from "../lib/dom-utils";
 import { applyEmphasisStyles, applyInitialStyles } from "../lib/styles";
 import { intersectors } from "./intersectors";
@@ -21,10 +22,19 @@ export async function clickElement(
 			}, 300);
 			(target.element as HTMLInputElement).focus();
 		} else {
+			// Sometimes websites use links with target="_blank" but don't open a new tab.
+			// They probably prevent the default behavior with javascript. For example Slack
+			// has this for opening a thread in the side panel. So here we make sure that
+			// if the main domains are equal just do a normal click and let the page handle it
+			const linkMainDomain = getMainDomain(
+				(target.element as HTMLLinkElement).href
+			);
+			const locationMainDomain = getMainDomain(window.location.href);
 			if (
 				target.element.tagName === "A" &&
 				(newTab ||
 					(target.element.getAttribute("target") === "_blank" &&
+						linkMainDomain !== locationMainDomain &&
 						(target.element as HTMLLinkElement).href &&
 						(target.element as HTMLLinkElement).href !== location.href))
 			) {
@@ -50,3 +60,17 @@ export async function clickElement(
 		}
 	}
 }
+
+function getMainDomain(url: string): string | undefined {
+	const parseResult = parseDomain(fromUrl(url));
+
+	// Check if the domain is listed in the public suffix list
+	if (parseResult.type === ParseResultType.Listed) {
+		const { domain, topLevelDomains } = parseResult;
+
+		const topLevel = topLevelDomains.join(".");
+		return `${domain!}.${topLevel}`;
+	}
+
+	return undefined;
+}