diff --git a/apps/opencs/view/tools/searchbox.cpp b/apps/opencs/view/tools/searchbox.cpp
index a2871b5489..9cfc2f3815 100644
--- a/apps/opencs/view/tools/searchbox.cpp
+++ b/apps/opencs/view/tools/searchbox.cpp
@@ -17,13 +17,21 @@ void CSVTools::SearchBox::updateSearchButton()
         switch (mMode.currentIndex())
         {
             case 0:
-            case 1:
             case 2:
-            case 3:
 
                 mSearch.setEnabled(!mText.text().isEmpty());
                 break;
 
+            case 1:
+            case 3:
+            {
+                if (mText.text().isEmpty())
+                    mSearch.setEnabled(false);
+                else
+                    mSearch.setEnabled(QRegularExpression(mText.text()).isValid());
+                break;
+            }
+
             case 4:
 
                 mSearch.setEnabled(true);