AboutWindow adjustments

Allow opening links in default browser
Close window on Esc
Add rounded corners

Window/AboutWindowController.swift

@@ -8,7 +8,7 @@
 import Cocoa
 import WebKit
 
-class AboutWindowController: NSWindowController {
+class AboutWindowController: NSWindowController, WKNavigationDelegate {
     
     @IBOutlet weak var appName: NSTextField!
     @IBOutlet weak var appVersion: NSTextField!
@@ -30,6 +30,8 @@ class AboutWindowController: NSWindowController {
         
         creditsView.setValue(false, forKey: "drawsBackground")
 
+        vfxView.wantsLayer = true
+        vfxView.layer?.cornerRadius = 4
 
         // fill up labels
         
@@ -49,6 +51,21 @@ class AboutWindowController: NSWindowController {
             
         }
         
-    }
+        creditsView.navigationDelegate = self
 
     }
+    
+    func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
+        if navigationAction.navigationType == .linkActivated,
+           let url = navigationAction.request.url {
+            NSWorkspace.shared.open(url)
+            decisionHandler(.cancel)
+            return
+        }
+        decisionHandler(.allow)
+    }
+
+    @objc func cancel(_ sender: Any?) {
+        close()
+    }
+}