Updated imgui to v1.91.8-docking.

3rdparty/imgui/examples/example_apple_opengl2/main.mm

@@ -1,6 +1,10 @@
 // Dear ImGui: standalone example application for OSX + OpenGL2, using legacy fixed pipeline
-// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
-// Read online: https://github.com/ocornut/imgui/tree/master/docs
+
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
 
 #import <Cocoa/Cocoa.h>
 #import <OpenGL/gl.h>