diff --git a/src/modules/grubcfg/grubcfg.conf b/src/modules/grubcfg/grubcfg.conf
index b354ec35a..ba31d6070 100644
--- a/src/modules/grubcfg/grubcfg.conf
+++ b/src/modules/grubcfg/grubcfg.conf
@@ -1,9 +1,12 @@
+# Create, overwrite or update /etc/default/grub in the target system.
+#
 # Write lines to /etc/default/grub (in the target system) based
 # on calculated values and the values set in the *defaults* key
 # in this configuration file.
 #
 # Calculated values are:
-#   - GRUB_DISTRIBUTOR,   branding module, *bootloaderEntryName*
+#   - GRUB_DISTRIBUTOR,   branding module, *bootloaderEntryName* (this
+#     string is sanitized, and see also setting *keepDistributor*)
 #   - GRUB_ENABLE_CRYPTODISK, based on the presence of filesystems
 #     that use LUKS
 #   - GRUB_CMDLINE_LINUX_DEFAULT, adding LUKS setup and plymouth
@@ -14,6 +17,12 @@
 # already existed. If set to false, edits the existing file instead.
 overwrite: false
 
+# If set to true, an **existing** setting for GRUB_DISTRIBUTOR is
+# kept, not updated to the *bootloaderEntryName* from the branding file.
+# Use this if the GRUB_DISTRIBUTOR setting in the file is "smart" in
+# some way (e.g. uses shell-command substitution).
+keepDistributor: false
+
 # Default entries to write to /etc/default/grub if it does not exist yet or if
 # we are overwriting it.
 #
diff --git a/src/modules/grubcfg/main.py b/src/modules/grubcfg/main.py
index 83441a736..1f2574965 100644
--- a/src/modules/grubcfg/main.py
+++ b/src/modules/grubcfg/main.py
@@ -45,7 +45,13 @@ def modify_grub_default(partitions, root_mount_point, distributor):
 
     :param partitions:
     :param root_mount_point:
-    :param distributor:
+    :param distributor: name of the distributor to fill in for
+        GRUB_DISTRIBUTOR. Must be a string. If the job setting
+        *keepDistributor* is set, then this is only used if no
+        GRUB_DISTRIBUTOR is found at all (otherwise, when *keepDistributor*
+        is set, the GRUB_DISTRIBUTOR lines are left unchanged).
+        If *keepDistributor* is unset or false, then GRUB_DISTRIBUTOR
+        is always updated to set this value.
     :return:
     """
     default_dir = os.path.join(root_mount_point, "etc/default")
@@ -172,8 +178,13 @@ def modify_grub_default(partitions, root_mount_point, distributor):
                 have_kernel_cmd = True
             elif (lines[i].startswith("#GRUB_DISTRIBUTOR")
                   or lines[i].startswith("GRUB_DISTRIBUTOR")):
-                lines[i] = distributor_line
-                have_distributor_line = True
+                if libcalamares.job.configuration.get("keepDistributor", false):
+                    lines[i] = distributor_line
+                    have_distributor_line = True
+                else:
+                    # We're not updating because of *keepDistributor*, but if
+                    # this was a comment line, then it's still not been set.
+                    have_distributor_line = have_distributor_line or not lines[i].startsdwith("#")
     else:
         lines = []
 
diff --git a/src/modules/grubcfg/tests/1.global b/src/modules/grubcfg/tests/1.global
new file mode 100644
index 000000000..02ae840cb
--- /dev/null
+++ b/src/modules/grubcfg/tests/1.global
@@ -0,0 +1,2 @@
+---
+bogus: true
diff --git a/src/modules/grubcfg/tests/2.global b/src/modules/grubcfg/tests/2.global
new file mode 100644
index 000000000..83e79db28
--- /dev/null
+++ b/src/modules/grubcfg/tests/2.global
@@ -0,0 +1,10 @@
+---
+bogus: true
+firmwareType: bios
+bootLoader: grub
+rootMountPoint: /tmp/calamares
+
+branding:
+  bootloaderEntryName: generic
+partitions: []
+
diff --git a/src/modules/grubcfg/tests/2.job b/src/modules/grubcfg/tests/2.job
new file mode 100644
index 000000000..d7b8db9d1
--- /dev/null
+++ b/src/modules/grubcfg/tests/2.job
@@ -0,0 +1,9 @@
+---
+overwrite: true
+keepDistributor: false
+defaults:
+    GRUB_TIMEOUT: 5
+    GRUB_DEFAULT: "saved"
+    GRUB_DISABLE_SUBMENU: true
+    GRUB_TERMINAL_OUTPUT: "console"
+    GRUB_DISABLE_RECOVERY: true