diff --git a/CHANGES/v2.8.md b/CHANGES/v2.8.md
index e59eb0c651..1735554306 100644
--- a/CHANGES/v2.8.md
+++ b/CHANGES/v2.8.md
@@ -105,3 +105,4 @@ Changes from version 2.7 which are relevant for users:
 ## Version 2.8.4
 - Added the possibility to disable `RTLD_DEEPBIND` (see \issue{952}).
 - Fixed a bug in `switchingfunction` mode `Q` thanks to @nm3787, (see #951)
+- Improved error reporting in CUSTOM switching function: an error is thrown if one uses `x` and `x2` arguments simultaneously (reported by Olivier Languin-Cattoen).