Merge pull request #67051 from clayjohn/CanvasGroup-clear

Allow clearing backbuffer after finishing CanvasGroup

drivers/gles3/rasterizer_canvas_gles3.cpp

@@ -300,6 +300,8 @@ void RasterizerCanvasGLES3::canvas_render_items(RID p_to_render_target, Item *p_
 			}
 
 			canvas_group_owner = nullptr;
+			// Backbuffer is dirty now and needs to be re-cleared if another CanvasGroup needs it.
+			backbuffer_cleared = false;
 		}
 
 		if (backbuffer_copy) {

servers/rendering/renderer_rd/renderer_canvas_render_rd.cpp

@@ -1475,6 +1475,8 @@ void RendererCanvasRenderRD::canvas_render_items(RID p_to_render_target, Item *p
 			}
 
 			canvas_group_owner = nullptr;
+			// Backbuffer is dirty now and needs to be re-cleared if another CanvasGroup needs it.
+			backbuffer_cleared = false;
 		}
 
 		if (backbuffer_copy) {