diff --git a/regression_testing/cases/dev-cases/case-0pg.conf copy b/regression_testing/cases/dev-cases/case-0pg.conf copy
new file mode 100755
index 0000000..dd7818a
--- /dev/null
+++ b/regression_testing/cases/dev-cases/case-0pg.conf copy	
@@ -0,0 +1,4 @@
+# Config for test case.
+tidy-mark: no
+indent: no
+wrap: 99999
diff --git a/regression_testing/cases/dev-cases/case-0pg@0.html b/regression_testing/cases/dev-cases/case-0pg@0.html
new file mode 100644
index 0000000..fec3c7f
--- /dev/null
+++ b/regression_testing/cases/dev-cases/case-0pg@0.html
@@ -0,0 +1,28 @@
+<!--
+This test case is for issue #523, in which a space is placed after the
+closing tag of certain elements. For example below, a space is added after
+the first script closing tag and after the img tag.
+ -->
+<!DOCTYPE html>
+<html>
+<head>
+<title>test</title>
+</head>
+<body>
+<script type="text/javascript">
+</script>
+<script type="text/javascript">
+</script>
+<h1>Hello</h1>
+<script type="text/javascript">
+</script>
+<img src="hi.jpg">
+<script type="text/javascript">
+</script>
+<p>This is a block level element, and as such, is capable of inlining inline elements.<script type="text/javascript">let x = "Hello, world"</script> Scripts are inline elements, so this script should be included in the flow.</p>
+<script type="text/javascript"></script><img src="bye.jpg"><script type="text/javascript"></script>
+<hr>
+<p>This is another paragraph with an <img src="meh.jpg"> tag inline.</p>
+<img src="one.jpg"><img src="two.jpg"><img src="three.jpg">
+</body>
+</html>
diff --git a/version.txt b/version.txt
index d320479..c010d3f 100644
--- a/version.txt
+++ b/version.txt
@@ -1,2 +1,2 @@
-5.9.16
-2021.08.23
+5.9.17
+2021.08.26
