running.md: Mention about issue with Nahimic on Windows

Let people know that they will need to use GTK with the Nahimic service
disabled or OpenGL disabled or put their GTK application into the Nahimic
backlist, or try to use GLES, since there is a known issue in the Windows
nVidia graphics drivers and Nahimic that causes GL operations to fail,
causing crashes in operations such as window resizes.

This will close issue #4113--sadly, there is nothing we can do within
GTK to fix the issue.

diff --git a/docs/reference/gtk/running.md b/docs/reference/gtk/running.md
index 446f01b227cd3ca29c33512c2f11bcd611b81370..fd6f3d235d0dc0921076e931bdaf0d0e23bf394e 100644 (file)
--- a/docs/reference/gtk/running.md
+++ b/docs/reference/gtk/running.md
@@ -339,6 +339,20 @@ using and the GDK backend supports them:
 `vulkan`
 : Selects the Vulkan renderer
 
+Note that on Windows, if one is running Nahimic 3 on a system with
+nVidia graphics, one needs to stop the "Nahimic service" or insert
+the GTK application into the Nahimic blacklist, as noted in
+https://www.nvidia.com/en-us/geforce/forums/game-ready-drivers/13/297952/nahimic-and-nvidia-drivers-conflict/2334568/, or use the cairo renderer (at the cost of being unable to use
+OpenGL features), or use GDK_DEBUG=gl-gles if you know that GLES
+support is enabled for the build.
+
+This is a known issue, as the above link indicates, and affects quite
+a number of applications--sadly, since this issue lies within the
+nVidia graphics driver and/or the Nahimic 3 code, we are not able
+to rememdy this on the GTK side; the best bet before trying the above
+workarounds is to try to update your graphics drivers and Nahimic
+installation.
+
 ### `GTK_CSD`
 
 The default value of this environment variable is `1`. If changed