Experiment: mark clicked links

FAQ.md

@@ -2811,7 +2811,7 @@ Reformatting and displaying such messages will take too long. You can try to use
 <a name="faq125"></a>
 **(125) What are the current experimental features?**
 
-* ...
+* Mark clicked links by changing the link color
 
 <br />
 

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

@@ -4114,8 +4114,15 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                         if (url.equals(title))
                             title = null;
 
-                        if (onOpenLink(uri, title))
+                        if (onOpenLink(uri, title)) {
+                            SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(widget.getContext());
+                            boolean experiments = prefs.getBoolean("experiments", false);
+                            if (experiments) {
+                                int colorPrimary = Helper.resolveColor(widget.getContext(), android.R.attr.textColorPrimary);
+                                buffer.setSpan(new ForegroundColorSpan(colorPrimary), start, end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+                            }
                             return true;
+                        }
                     }
 
                     ImageSpan[] image = buffer.getSpans(off, off, ImageSpan.class);