diff --git a/packages/client-app/internal_packages/composer-signature/styles/composer-signature.less b/packages/client-app/internal_packages/composer-signature/styles/composer-signature.less
index 1c0dc9a787..48a7071ccb 100644
--- a/packages/client-app/internal_packages/composer-signature/styles/composer-signature.less
+++ b/packages/client-app/internal_packages/composer-signature/styles/composer-signature.less
@@ -87,6 +87,8 @@
       flex: 1;
       font-family: monospace;
       font-size: 0.9em;
+      width: 100%;
+      height: 100%;
     }
 
     .contenteditable {