diff --git a/DESCRIPTION b/DESCRIPTION
index 8ed38da2c..5eadd8ee7 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: bookdown
 Type: Package
 Title: Authoring Books and Technical Documents with R Markdown
-Version: 0.37.1
+Version: 0.37.2
 Authors@R: c(
     person("Yihui", "Xie", role = c("aut", "cre"), email = "xie@yihui.name", comment = c(ORCID = "0000-0003-0645-5666")),
     person("Christophe", "Dervieux", , "cderv@posit.co", role = c("ctb"),
diff --git a/NEWS.md b/NEWS.md
index 39b54de83..9e3526684 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,5 +1,6 @@
 # CHANGES IN bookdown VERSION 0.38
 
+- Fixed a bug that `gitbook()` may geneate an empty search index on certain platforms (thanks, @UlvHare, #1454).
 
 # CHANGES IN bookdown VERSION 0.37
 
diff --git a/R/utils.R b/R/utils.R
index b23a09dfb..60ba53f57 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -263,7 +263,7 @@ clean_meta = function(meta_file, files) {
 
 # remove HTML tags and remove extra spaces
 strip_html = function(x) {
-  gsub('\\s{2,}', ' ', xfun::strip_html(x))
+  gsub('\\s{2,}', ' ', xfun::strip_html(x), perl = TRUE)
 }
 
 # remove the <script><script> content and references