From b36e555e685cb4347955f6042e67fd4ddf174664 Mon Sep 17 00:00:00 2001
From: Nyall Dawson <nyall.dawson@gmail.com>
Date: Fri, 6 Oct 2023 13:41:05 +1000
Subject: [PATCH] When mapping color for rendering highlighted (identified)
 features, don't allow pixels which were previously non-transparent to become
 totally transparent.

This can result in invisible highlights for very transparent symbols.

Fixes #54830
---
 src/gui/qgshighlight.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/gui/qgshighlight.cpp b/src/gui/qgshighlight.cpp
index ed1fa1c45dcb..23fd06825330 100644
--- a/src/gui/qgshighlight.cpp
+++ b/src/gui/qgshighlight.cpp
@@ -393,7 +393,7 @@ void QgsHighlight::paint( QPainter *p )
           if ( alpha > 0 )
           {
             int green = qGreen( line[c] );
-            line[c] = qRgba( penRed, penGreen, penBlue, std::clamp( static_cast< int >( alpha - ( green * k ) ), 0, 255 ) );
+            line[c] = qRgba( penRed, penGreen, penBlue, std::clamp( static_cast< int >( alpha - ( green * k ) ), 30, 255 ) );
           }
         }
       }