diff --git a/polymer/eduke32/build/include/editor.h b/polymer/eduke32/build/include/editor.h
index ab9b1e50d..db6354df5 100644
--- a/polymer/eduke32/build/include/editor.h
+++ b/polymer/eduke32/build/include/editor.h
@@ -328,6 +328,7 @@ void update_highlight(void);
 void update_highlightsector(void);
 void reset_highlightsector(void);
 void reset_highlight(void);
+void handlesecthighlight1(int32_t i, int32_t sub, int32_t nograycheck);
 void ovh_whiteoutgrab(int32_t restoreredwalls);
 
 int32_t inside_editor_curpos(int16_t sectnum);
diff --git a/polymer/eduke32/build/src/build.c b/polymer/eduke32/build/src/build.c
index bc41249e8..647374362 100644
--- a/polymer/eduke32/build/src/build.c
+++ b/polymer/eduke32/build/src/build.c
@@ -2831,7 +2831,7 @@ void SetFirstWall(int32_t sectnum, int32_t wallnum, int32_t alsoynw)
     asksave = 1;
 }
 
-static void handlesecthighlight1(int32_t i, int32_t sub, int32_t nograycheck)
+void handlesecthighlight1(int32_t i, int32_t sub, int32_t nograycheck)
 {
     int32_t j;
 
diff --git a/polymer/eduke32/source/astub.c b/polymer/eduke32/source/astub.c
index 2bd3d3f32..6ad231f98 100644
--- a/polymer/eduke32/source/astub.c
+++ b/polymer/eduke32/source/astub.c
@@ -4430,6 +4430,28 @@ static void Keys3d(void)
 
     VM_OnEvent(EVENT_PREKEYS3D, -1);
 
+    if (keystatus[KEYSC_RALT] && keystatus[KEYSC_RCTRL] && AIMING_AT_CEILING_OR_FLOOR && searchsector >= 0)
+    {
+        keystatus[KEYSC_RALT] = 0;
+
+        if (highlightcnt >= 0)
+        {
+            message("WARNING: Cannot select sectors while sprites/walls selected");
+        }
+        else
+        {
+            const int32_t sub = keystatus[KEYSC_SEMI];
+            const int32_t add = keystatus[KEYSC_QUOTE];
+
+            if (!add && !sub)
+                reset_highlightsector();
+
+            handlesecthighlight1(searchsector, sub, 1);
+
+            message("%s sector %d", sub ? "De-selected" : "Selected", searchsector);
+        }
+    }
+
     if (keystatus[KEYSC_QUOTE] && PRESSED_KEYSC(V)) // ' V
     {
         if (AIMING_AT_CEILING_OR_FLOOR)