Saving caret position when using external editor, attempting to restore it on window activation. Fixes #4155

Author: Federico Fissore

app/src/processing/app/Base.java

@@ -613,7 +613,11 @@ protected void handleActivated(Editor whichEditor) {
     activeEditor.rebuildRecentSketchesMenu();
     if (PreferencesData.getBoolean("editor.external")) {
       try {
+        int previousCaretPosition = activeEditor.getTextArea().getCaretPosition();
         activeEditor.getSketch().load(true);
+        if (previousCaretPosition < activeEditor.getText().length()) {
+          activeEditor.getTextArea().setCaretPosition(previousCaretPosition);
+        }
       } catch (IOException e) {
         // noop
       }