diff --git a/.stylelintrc.js b/.stylelintrc.js
index 97e1ec8023..f028c76cc0 100644
--- a/.stylelintrc.js
+++ b/.stylelintrc.js
@@ -15,6 +15,9 @@ module.exports = {
         "number-leading-zero": null,
         "selector-list-comma-newline-after": null,
         "at-rule-no-unknown": null,
-        "scss/at-rule-no-unknown": true,
+        "scss/at-rule-no-unknown": [true, {
+            // https://github.com/vector-im/riot-web/issues/10544
+            "ignoreAtRules": ["define-mixin"],
+        }],
     }
 }