diff -up chromium-91.0.4472.77/chrome/browser/first_run/first_run_internal_linux.cc.etc chromium-91.0.4472.77/chrome/browser/first_run/first_run_internal_linux.cc
--- chromium-91.0.4472.77/chrome/browser/first_run/first_run_internal_linux.cc.etc	2021-06-01 16:37:39.182531036 -0400
+++ chromium-91.0.4472.77/chrome/browser/first_run/first_run_internal_linux.cc	2021-06-01 16:39:31.590102809 -0400
@@ -20,9 +20,9 @@ bool IsOrganicFirstRun() {
 
 base::FilePath InitialPrefsPath() {
   // The standard location of the initial prefs is next to the chrome binary.
+  // ...but we patch it to use /etc/chromium
   base::FilePath initial_prefs;
-  if (!base::PathService::Get(base::DIR_EXE, &initial_prefs))
-    return base::FilePath();
+  initial_prefs = base::FilePath("/etc/chromium");
 
   base::FilePath new_path = initial_prefs.AppendASCII(installer::kInitialPrefs);
   if (base::PathIsReadable(new_path))