common/static/common/styles/studio/_comments.sass

@@ -48,10 +48,6 @@
   +margin(2, bottom)
   +margin(2, top)
 
-.comment-input-div,
-.comment-send
-  height: calc(var(--spacer) * 2.5)
-
 .comment-input-div
   @extend .form-control
 

common/static/common/styles/studio/_web-assets-overrides.sass

@@ -194,6 +194,11 @@ details
     padding-right: var(--spacer-2) !important
 
 /* Forms. */
+input,
+.form-control
+  height: auto
+  min-height: calc(var(--spacer) * 2.5)
+
 .form-control
   border: 0 // Make btn and input heights match in horizontal layouts
   background-color: var(--color-bg-secondary)