diff --git a/app/styles/components/compose-form.scss b/app/styles/components/compose-form.scss
index ee31b8f66..af736a19a 100644
--- a/app/styles/components/compose-form.scss
+++ b/app/styles/components/compose-form.scss
@@ -299,6 +299,7 @@
     .compose-form__upload-thumbnail {
       border-radius: 4px;
       background-position: center;
+      background-size: contain;
       background-repeat: no-repeat;
       height: 160px;
       width: 100%;