diff --git a/app/internal_packages/composer-signature/styles/composer-signature.less b/app/internal_packages/composer-signature/styles/composer-signature.less
index 1c0dc9a78..258f0548a 100644
--- a/app/internal_packages/composer-signature/styles/composer-signature.less
+++ b/app/internal_packages/composer-signature/styles/composer-signature.less
@@ -82,6 +82,8 @@
     }
 
     textarea {
+      width: 100%;
+      height: 100%;
       padding: 10px;
       border: 0;
       flex: 1;