diff -ruN ecl-21.2.1/src/doc/manual/Makefile ecl-21.2.1.new/src/doc/manual/Makefile
--- src/doc/manual/Makefile	2021-02-01 13:59:46.000000000 +0100
+++ src/doc/manual/Makefile	2023-03-03 15:39:58.868387858 +0100
@@ -18,7 +18,7 @@
 html/index.html: $(FILES)
 	$(MAKEINFO) --html --css-include=ecl.css --split=section manual.txi
 	rm -rf html
-	mv ecl html
+	mv ecl_html html
 	cp -r figures html
 
 clean: