--- a/plugins/color/gsd-color-state.c
+++ b/plugins/color/gsd-color-state.c
@@ -2,7 +2,6 @@
  *
  * Copyright (C) 2007 William Jon McCann <mccann@jhu.edu>
  * Copyright (C) 2011-2013 Richard Hughes <richard@hughsie.com>
- * Copyright (C) 2020 NVIDIA CORPORATION
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -27,7 +26,6 @@
 #include <stdlib.h>
 #include <lcms2.h>
 #include <canberra-gtk.h>
-#include <math.h>
 
 #define GNOME_DESKTOP_USE_UNSTABLE_API
 #include <libgnome-desktop/gnome-rr.h>
@@ -128,47 +126,8 @@
         return edid;
 }
 
-static CdIcc *
-gcm_get_srgb_icc (GError **error)
-{
-        /* load the reference sRGB profile */
-        CdIcc *srgb_icc = cd_icc_new ();
-        if (!srgb_icc)
-                return NULL;
-
-        if (!cd_icc_create_default_full (srgb_icc,
-                                         CD_ICC_LOAD_FLAGS_PRIMARIES,
-                                         error)) {
-                g_object_unref (srgb_icc);
-                return NULL;
-        }
-
-        return srgb_icc;
-}
-
-static char *
-gcm_get_srgb_bytes (gsize *length,
-                    GError **error)
-{
-        g_autoptr(CdIcc) srgb_icc = NULL;
-        GBytes *bytes;
-
-        srgb_icc = gcm_get_srgb_icc (error);
-        if (srgb_icc == NULL)
-                return NULL;
-
-        bytes = cd_icc_save_data (srgb_icc,
-                                  CD_ICC_SAVE_FLAGS_NONE,
-                                  error);
-        if (bytes == NULL)
-                return NULL;
-
-        return g_bytes_unref_to_data (bytes, length);
-}
-
 static gboolean
 gcm_session_screen_set_icc_profile (GsdColorState *state,
-                                    GnomeRROutput *output,
                                     const gchar *filename,
                                     GError **error)
 {
@@ -186,21 +145,9 @@
 
         g_debug ("setting root window ICC profile atom from %s", filename);
 
-        if (gnome_rr_output_supports_color_transform (output)) {
-                /*
-                 * If the window system supports color transforms, then
-                 * applications should use the standard sRGB color profile and
-                 * the window system will take care of converting colors to
-                 * match the output device's measured color profile.
-                 */
-                data = gcm_get_srgb_bytes (&length, error);
-                if (data == NULL)
-                        return FALSE;
-        } else {
-                /* get contents of file */
-                if (!g_file_get_contents (filename, &data, &length, error))
-                        return FALSE;
-        }
+        /* get contents of file */
+        if (!g_file_get_contents (filename, &data, &length, error))
+                return FALSE;
 
         /* set profile property */
         gdk_property_change (state->gdk_window,
@@ -485,71 +432,6 @@
         return ret;
 }
 
-static uint64_t
-gcm_double_to_ctmval (double value)
-{
-        uint64_t sign = value < 0;
-        double integer, fractional;
-
-        if (sign)
-                value = -value;
-
-        fractional = modf (value, &integer);
-
-        return sign << 63 |
-               (uint64_t) integer << 32 |
-               (uint64_t) (fractional * 0xffffffffUL);
-}
-
-static GnomeRRCTM
-gcm_mat33_to_ctm (CdMat3x3 matrix)
-{
-        GnomeRRCTM ctm;
-
-        /*
-         * libcolord generates a matrix containing double values. RandR's CTM
-         * property expects values in S31.32 fixed-point sign-magnitude format
-         */
-        ctm.matrix[0] = gcm_double_to_ctmval (matrix.m00);
-        ctm.matrix[1] = gcm_double_to_ctmval (matrix.m01);
-        ctm.matrix[2] = gcm_double_to_ctmval (matrix.m02);
-        ctm.matrix[3] = gcm_double_to_ctmval (matrix.m10);
-        ctm.matrix[4] = gcm_double_to_ctmval (matrix.m11);
-        ctm.matrix[5] = gcm_double_to_ctmval (matrix.m12);
-        ctm.matrix[6] = gcm_double_to_ctmval (matrix.m20);
-        ctm.matrix[7] = gcm_double_to_ctmval (matrix.m21);
-        ctm.matrix[8] = gcm_double_to_ctmval (matrix.m22);
-
-        return ctm;
-}
-
-static gboolean
-gcm_set_csc_matrix (GnomeRROutput *output,
-                    CdProfile *profile,
-                    GError **error)
-{
-        g_autoptr(CdIcc) icc = NULL;
-        g_autoptr(CdIcc) srgb_icc = NULL;
-        CdMat3x3 csc;
-        GnomeRRCTM ctm;
-
-        /* open file */
-        icc = cd_profile_load_icc (profile, CD_ICC_LOAD_FLAGS_PRIMARIES, NULL,
-                                   error);
-        if (icc == NULL)
-                return FALSE;
-
-        srgb_icc = gcm_get_srgb_icc (error);
-        if (srgb_icc == NULL)
-                return FALSE;
-
-        if (!cd_icc_utils_get_adaptation_matrix (icc, srgb_icc, &csc, error))
-                return FALSE;
-
-        ctm = gcm_mat33_to_ctm (csc);
-        return gnome_rr_output_set_color_transform (output, ctm, error);
-}
-
 static GPtrArray *
 gcm_session_generate_vcgt (CdProfile *profile, guint color_temperature, guint size)
 {
@@ -923,7 +805,6 @@
         ret = gcm_session_use_output_profile_for_screen (state, output);
         if (ret) {
                 ret = gcm_session_screen_set_icc_profile (state,
-                                                          output,
                                                           filename,
                                                           &error);
                 if (!ret) {
@@ -959,20 +840,6 @@
                         goto out;
                 }
         }
-
-        if (gnome_rr_output_supports_color_transform (output)) {
-                ret = gcm_set_csc_matrix (output,
-                                          profile,
-                                          &error);
-                if (!ret) {
-                        g_warning ("failed to set %s color transform matrix: %s",
-                                   cd_device_get_id (helper->device),
-                                   error->message);
-                        g_error_free (error);
-                        goto out;
-                }
-        }
-
 out:
         gcm_session_async_helper_free (helper);
 }