diff --git a/app/pdb/image-color-profile-cmds.c b/app/pdb/image-color-profile-cmds.c
index 806bbd2e95..855f081dbc 100644
--- a/app/pdb/image-color-profile-cmds.c
+++ b/app/pdb/image-color-profile-cmds.c
@@ -143,7 +143,7 @@ image_set_color_profile_invoker (GimpProcedure         *procedure,
 
   if (success)
     {
-      if (color_profile)
+      if (color_profile && g_bytes_get_size (color_profile) > 0)
         {
           GimpColorProfile *profile;
 
@@ -272,7 +272,7 @@ image_set_simulation_profile_invoker (GimpProcedure         *procedure,
 
   if (success)
     {
-      if (color_profile)
+      if (color_profile && g_bytes_get_size (color_profile) > 0)
         {
           GimpColorProfile *profile;
 
diff --git a/libgimp/gimpimagecolorprofile.c b/libgimp/gimpimagecolorprofile.c
index 71c99b56f0..ff7894dfdc 100644
--- a/libgimp/gimpimagecolorprofile.c
+++ b/libgimp/gimpimagecolorprofile.c
@@ -67,6 +67,9 @@ gimp_image_get_color_profile (GimpImage *image)
  *
  * This procedure sets the image's color profile.
  *
+ * If %NULL is passed as @profile, then the built-in profile for
+ * @image's color model is set.
+ *
  * Returns: %TRUE on success.
  *
  * Since: 2.10
@@ -140,6 +143,8 @@ gimp_image_get_simulation_profile (GimpImage *image)
  *
  * This procedure sets the image's simulation color profile.
  *
+ * If %NULL is passed as @profile, then the simulation profile is unset.
+ *
  * Returns: %TRUE on success.
  *
  * Since: 3.0
diff --git a/libgimp/gimpimagecolorprofile_pdb.c b/libgimp/gimpimagecolorprofile_pdb.c
index 0ce5d6ee22..635ec010ba 100644
--- a/libgimp/gimpimagecolorprofile_pdb.c
+++ b/libgimp/gimpimagecolorprofile_pdb.c
@@ -116,7 +116,7 @@ _gimp_image_get_effective_color_profile (GimpImage *image)
 /**
  * _gimp_image_set_color_profile:
  * @image: The image.
- * @color_profile: The new serialized color profile.
+ * @color_profile: (nullable): The new serialized color profile.
  *
  * Sets the image's color profile
  *
@@ -238,7 +238,7 @@ _gimp_image_get_simulation_profile (GimpImage *image)
 /**
  * _gimp_image_set_simulation_profile:
  * @image: The image.
- * @color_profile: The new serialized simulation color profile.
+ * @color_profile: (nullable): The new serialized simulation color profile.
  *
  * Sets the image's simulation color profile
  *
diff --git a/pdb/groups/image_color_profile.pdb b/pdb/groups/image_color_profile.pdb
index 8f2f81bae6..bbbbf420d2 100644
--- a/pdb/groups/image_color_profile.pdb
+++ b/pdb/groups/image_color_profile.pdb
@@ -122,14 +122,14 @@ HELP
     @inargs = (
         { name => 'image', type => 'image',
           desc => 'The image' },
-        { name => 'color_profile', type => 'bytes',
+        { name => 'color_profile', type => 'bytes', none_ok => 1,
           desc => 'The new serialized color profile' }
     );
 
     %invoke = (
         code => <<'CODE'
 {
-  if (color_profile)
+  if (color_profile && g_bytes_get_size (color_profile) > 0)
     {
       GimpColorProfile *profile;
 
@@ -263,14 +263,14 @@ HELP
     @inargs = (
         { name => 'image', type => 'image',
           desc => 'The image' },
-        { name => 'color_profile', type => 'bytes',
+        { name => 'color_profile', type => 'bytes', none_ok => 1,
           desc => 'The new serialized simulation color profile'}
     );
 
     %invoke = (
         code => <<'CODE'
 {
-  if (color_profile)
+  if (color_profile && g_bytes_get_size (color_profile) > 0)
     {
       GimpColorProfile *profile;