diff --git a/master_changes.md b/master_changes.md
index 44fd4c437ea..136b0303757 100644
--- a/master_changes.md
+++ b/master_changes.md
@@ -65,6 +65,9 @@ users)
 ## Exec
   * [NEW] Add `opam exec --no-switch` [#4957 @kit-ty-kate - fix #4951]
 
+## Env
+  * Revert environment variables instead of setting them to an empty string [#5039 @rjbou]
+
 ## Lint
   * W68: add warning for missing license field [#4766 @kit-ty-kate - partial fix #4598]
   * W62: use the spdx_licenses library to check for valid licenses. This allows to use compound expressions such as "MIT AND (GPL-2.0-only OR LGPL-2.0-only)", as well as user defined licenses e.g. "LicenseRef-my-custom-license" [#4768 @kit-ty-kate - fixes #4598]