diff --git a/ChangeLog b/ChangeLog
index 62b332aae..63034fb5a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2024-04-01  Bart Schaefer  <schaefer@zsh.org>
+
+	* 52781 (and typo fix): Src/hashtable.c: HIST IGNORE_DUPS treats
+	whitespace as significant when HIST_REDUCE_BLANKS is also set.
+
 2024-04-01  Oliver Kiddle  <opk@zsh.org>
 
 	* github #115: OKURA Masafumi: Completion/Unix/Command/_ruby:
diff --git a/Src/hashtable.c b/Src/hashtable.c
index 75b06c4ad..96675a393 100644
--- a/Src/hashtable.c
+++ b/Src/hashtable.c
@@ -1397,6 +1397,14 @@ histstrcmp(const char *str1, const char *str2)
 {
     while (inblank(*str1)) str1++;
     while (inblank(*str2)) str2++;
+
+    /* If insignificant whitespace has already been eliminated,
+     * there is no reason to expend similar effort here.  Also,
+     * this is more accurate in cases of quoted whitespace.
+     */
+    if (isset(HISTREDUCEBLANKS))
+	return strcmp(str1, str2);
+
     while (*str1 && *str2) {
 	if (inblank(*str1)) {
 	    if (!inblank(*str2))