diff --git a/scss/forms/_input-group.scss b/scss/forms/_input-group.scss
index a37dd8e737..f729d0bd2b 100644
--- a/scss/forms/_input-group.scss
+++ b/scss/forms/_input-group.scss
@@ -15,7 +15,8 @@
   > .form-select,
   > .form-file {
     position: relative; // For focus state's z-index
-    flex: 1 1 0%;
+    flex: 1 1 auto;
+    width: 1%;
     min-width: 0; // https://stackoverflow.com/questions/36247140/why-dont-flex-items-shrink-past-content-size
     margin-bottom: 0;