diff --git a/static/bootstrap/stylesheets/bootstrap/mixins/_progress-bar.scss b/static/bootstrap/stylesheets/bootstrap/mixins/_progress-bar.scss
new file mode 100644
index 0000000000000000000000000000000000000000..90a62afc2d6b33de932ff21247b9ef7eec258cf6
--- /dev/null
+++ b/static/bootstrap/stylesheets/bootstrap/mixins/_progress-bar.scss
@@ -0,0 +1,10 @@
+// Progress bars
+
+@mixin progress-bar-variant($color) {
+  background-color: $color;
+
+  // Deprecated parent class requirement as of v3.2.0
+  .progress-striped & {
+    @include gradient-striped;
+  }
+}