The ruler cursor (short vertical stroke at selection) should not change color...

... during play or record.

That bug was introduced at b19ed258e963c9342f0a573a3f054d9a8336f7fa

src/AColor.cpp

@@ -17,16 +17,32 @@ It is also a place to document colour usage policy in Audacity
 
 *//********************************************************************/
 
+#include "Audacity.h"
+#include "AColor.h"
+
 #include <wx/colour.h>
 #include <wx/dc.h>
 #include <wx/settings.h>
 #include <wx/utils.h>
 
-#include "AColor.h"
 #include "Theme.h"
 #include "Experimental.h"
 #include "AllThemeResources.h"
 
+void DCUnchanger::operator () (wxDC *pDC) const
+{
+   if (pDC) {
+      pDC->SetPen(pen);
+      pDC->SetBrush(brush);
+      pDC->SetLogicalFunction(wxRasterOperationMode(logicalOperation));
+   }
+}
+
+ADCChanger::ADCChanger(wxDC *pDC)
+   : Base{ pDC, ::DCUnchanger{ pDC->GetBrush(), pDC->GetPen(),
+      long(pDC->GetLogicalFunction()) } }
+{}
+
 bool AColor::inited = false;
 wxBrush AColor::lightBrush[2];
 wxBrush AColor::mediumBrush[2];

src/AColor.h

@@ -14,12 +14,39 @@
 #ifndef __AUDACITY_COLOR__
 #define __AUDACITY_COLOR__
 
+#include "MemoryX.h"
 #include <wx/brush.h>
 #include <wx/pen.h>
 
 class wxDC;
 class wxRect;
 
+struct DCUnchanger {
+public:
+   DCUnchanger() {}
+
+   DCUnchanger(const wxBrush &brush_, const wxPen &pen_, long logicalOperation_)
+   : brush(brush_), pen(pen_), logicalOperation(logicalOperation_)
+   {}
+
+   void operator () (wxDC *pDC) const;
+
+   wxBrush brush {};
+   wxPen pen {};
+   long logicalOperation {};
+};
+
+// Like wxDCPenChanger, etc., but simple and general
+// Make temporary drawing context changes that you back out of, RAII style
+
+class ADCChanger : public std::unique_ptr<wxDC, ::DCUnchanger>
+{
+   using Base = std::unique_ptr<wxDC, ::DCUnchanger>;
+public:
+   ADCChanger() : Base{} {}
+   ADCChanger(wxDC *pDC);
+};
+
 class AColor {
  public:
 

src/widgets/Ruler.cpp

@@ -3234,6 +3234,7 @@ void AdornedRulerPanel::DrawIndicator( double time, bool rec )
 void AdornedRulerPanel::DoDrawIndicator
    (wxDC * dc, double time, bool playing, int width, bool scrub)
 {
+   ADCChanger changer(dc); // Undo pen and brush changes at function exit
 
    const int x = Time2Pos(time);
    AColor::IndicatorColor( dc, playing );