Refactoring

app/src/main/java/eu/faircode/email/FragmentAnswer.java

@@ -498,7 +498,7 @@ public class FragmentAnswer extends FragmentBase {
             args.putInt("start", etText.getSelectionStart());
             args.putInt("end", etText.getSelectionEnd());
 
-            FragmentDialogLink fragment = new FragmentDialogLink();
+            FragmentDialogInsertLink fragment = new FragmentDialogInsertLink();
             fragment.setArguments(args);
             fragment.setTargetFragment(this, REQUEST_LINK);
             fragment.show(getParentFragmentManager(), "answer:link");

app/src/main/java/eu/faircode/email/FragmentCompose.java

@@ -1831,7 +1831,7 @@ public class FragmentCompose extends FragmentBase {
         args.putInt("start", etBody.getSelectionStart());
         args.putInt("end", etBody.getSelectionEnd());
 
-        FragmentDialogLink fragment = new FragmentDialogLink();
+        FragmentDialogInsertLink fragment = new FragmentDialogInsertLink();
         fragment.setArguments(args);
         fragment.setTargetFragment(this, REQUEST_LINK);
         fragment.show(getParentFragmentManager(), "compose:link");

app/src/main/java/eu/faircode/email/FragmentDialogInsertLink.java

@@ -36,7 +36,7 @@ import androidx.appcompat.app.AlertDialog;
 
 import static android.app.Activity.RESULT_OK;
 
-public class FragmentDialogLink extends FragmentDialogBase {
+public class FragmentDialogInsertLink extends FragmentDialogBase {
     private EditText etLink;
 
     @Override

app/src/main/java/eu/faircode/email/FragmentDialogOpenLink.java

@@ -309,9 +309,10 @@ public class FragmentDialogOpenLink extends FragmentDialogBase {
         String host = uri.getHost();
         String thost = (uriTitle == null ? null : uriTitle.getHost());
 
-        String puny;
+        String puny = null;
         try {
-            puny = IDN.toASCII(host);
+            if (host != null)
+                puny = IDN.toASCII(host, IDN.ALLOW_UNASSIGNED);
         } catch (Throwable ex) {
             Log.e(ex);
             puny = host;
@@ -322,7 +323,7 @@ public class FragmentDialogOpenLink extends FragmentDialogBase {
             tvSuspicious.setVisibility(View.VISIBLE);
         } else {
             etLink.setText(uri.toString());
-            tvSuspicious.setVisibility(View.GONE);
+            tvSuspicious.setVisibility(Helper.isSingleScript(host) ? View.GONE : View.VISIBLE);
         }
 
         grpDifferent.setVisibility(

app/src/main/java/eu/faircode/email/Helper.java

@@ -1113,6 +1113,10 @@ public class Helper {
 
     static boolean isSingleScript(String s) {
         // https://en.wikipedia.org/wiki/IDN_homograph_attack
+
+        if (TextUtils.isEmpty(s))
+            return true;
+
         if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N)
             return true;
 

app/src/main/java/eu/faircode/email/MessageHelper.java

@@ -1580,7 +1580,7 @@ public class MessageHelper {
             String domain = email.substring(at + 1);
 
             try {
-                user = IDN.toASCII(user);
+                user = IDN.toASCII(user, IDN.ALLOW_UNASSIGNED);
             } catch (IllegalArgumentException ex) {
                 Log.e(ex);
             }
@@ -1588,7 +1588,7 @@ public class MessageHelper {
             String[] parts = domain.split("\\.");
             for (int p = 0; p < parts.length; p++)
                 try {
-                    parts[p] = IDN.toASCII(parts[p]);
+                    parts[p] = IDN.toASCII(parts[p], IDN.ALLOW_UNASSIGNED);
                 } catch (IllegalArgumentException ex) {
                     Log.e(ex);
                 }