diff --git a/ChangeLog b/ChangeLog
index 1b6f3023..00ad7950 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -19,6 +19,7 @@
 - add vips_profile_load() and use it everywhere
 - fix race in temp filename creation [lhecker]
 - add @reduction_effort param to webpsave [lovell]
+- add @option_string param to thumbnail_buffer [kleisauke]
 
 4/1/19 started 8.7.4
 - magickload with magick6 API did not chain exceptions correctly causing a
diff --git a/libvips/resample/thumbnail.c b/libvips/resample/thumbnail.c
index 50b702ff..04e535d4 100644
--- a/libvips/resample/thumbnail.c
+++ b/libvips/resample/thumbnail.c
@@ -16,6 +16,8 @@
  * 	- implement shrink-on-load for openslide images
  * 16/11/18
  * 	- implement shrink-on-load for tiff pyramid 
+ * 3/2/19 kleisauke
+ * 	- add option_string param to thumbnail_buffer
  */
 
 /*