diff --git a/other/nightly/upgrade.sh b/other/nightly/upgrade.sh
index 35c087db69..fea3c360c7 100644
--- a/other/nightly/upgrade.sh
+++ b/other/nightly/upgrade.sh
@@ -228,6 +228,9 @@ quote_root_user_env_values() {
     local key value
     for key in ROOT_USERNAME ROOT_USER_EMAIL ROOT_USER_PASSWORD; do
         value=$(grep -m1 "^${key}=" "$ENV_FILE" | cut -d '=' -f2-) || continue
+        # phpdotenv ignores whitespace around an unquoted value (also the \r of CRLF line endings)
+        value="${value#"${value%%[![:space:]]*}"}"
+        value="${value%"${value##*[![:space:]]}"}"
         case "$value" in
         \"* | \'* | *[[:space:]]\#*) continue ;;
         *[[:space:]]*) ;;
diff --git a/scripts/upgrade.sh b/scripts/upgrade.sh
index 9377d79c5a..e39f6378e7 100644
--- a/scripts/upgrade.sh
+++ b/scripts/upgrade.sh
@@ -228,6 +228,9 @@ quote_root_user_env_values() {
     local key value
     for key in ROOT_USERNAME ROOT_USER_EMAIL ROOT_USER_PASSWORD; do
         value=$(grep -m1 "^${key}=" "$ENV_FILE" | cut -d '=' -f2-) || continue
+        # phpdotenv ignores whitespace around an unquoted value (also the \r of CRLF line endings)
+        value="${value#"${value%%[![:space:]]*}"}"
+        value="${value%"${value##*[![:space:]]}"}"
         case "$value" in
         \"* | \'* | *[[:space:]]\#*) continue ;;
         *[[:space:]]*) ;;
diff --git a/tests/Unit/UpgradeScriptRootUserEnvTest.php b/tests/Unit/UpgradeScriptRootUserEnvTest.php
index e77ea3f6a2..6829e17155 100644
--- a/tests/Unit/UpgradeScriptRootUserEnvTest.php
+++ b/tests/Unit/UpgradeScriptRootUserEnvTest.php
@@ -65,3 +65,15 @@ it('keeps root user credentials that already parse unchanged', function (string
 
     expect(repairRootUserEnvWithUpgradeScript($scriptPath, $initialEnv))->toBe($initialEnv);
 })->with($upgradeScripts);
+
+it('keeps root user credentials that only have whitespace around the value unchanged', function (string $scriptPath) {
+    $initialEnv = "ROOT_USER_EMAIL=admin@example.com\r\nROOT_USERNAME= Jane\r\nROOT_USER_PASSWORD=Secret1!  \r\nAPP_ENV=production\r\n";
+
+    expect(repairRootUserEnvWithUpgradeScript($scriptPath, $initialEnv))->toBe($initialEnv);
+})->with($upgradeScripts);
+
+it('quotes a root username with spaces in a file with CRLF line endings', function (string $scriptPath) {
+    $env = repairRootUserEnvWithUpgradeScript($scriptPath, "ROOT_USERNAME=Jane Doe\r\nAPP_ENV=production\r\n");
+
+    expect(Dotenv::parse($env))->toBe(['ROOT_USERNAME' => 'Jane Doe', 'APP_ENV' => 'production']);
+})->with($upgradeScripts);