diff --git a/src/main/java/me/hatter/tools/secureeditor/Main.java b/src/main/java/me/hatter/tools/secureeditor/Main.java
index 87a4a99..fe58dab 100644
--- a/src/main/java/me/hatter/tools/secureeditor/Main.java
+++ b/src/main/java/me/hatter/tools/secureeditor/Main.java
@@ -36,7 +36,10 @@ public class Main {
 
         final Bytes decrypted = AESCryptTool.gcmDecrypt(keyBytes, nonceBytes).from(file).toBytes();
 
-        final boolean readonly = StringUtil.isOn(System.getProperty("readonly"));
+        final boolean readonly = StringUtil.isOn(StringUtil.def(
+                System.getenv("READONLY"),
+                System.getProperty("readonly"))
+        );
         final FutureResult futureResult = showWindow("Secure edit file",
                 decrypted.string(),
                 "File is encrypted in temp file",