diff --git a/src/main/resources/templates/about.html b/src/main/resources/templates/about.html
index c315ce74..1ae7ede3 100644
--- a/src/main/resources/templates/about.html
+++ b/src/main/resources/templates/about.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title='<3')}"></th:block>
   </head>
diff --git a/src/main/resources/templates/account.html b/src/main/resources/templates/account.html
index e07050ff..70fbc4fd 100644
--- a/src/main/resources/templates/account.html
+++ b/src/main/resources/templates/account.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{account.title})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/addUsers.html b/src/main/resources/templates/addUsers.html
index 4657ecd9..0cb5c512 100644
--- a/src/main/resources/templates/addUsers.html
+++ b/src/main/resources/templates/addUsers.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{adminUserSettings.title}, header=#{adminUserSettings.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/auto-split-pdf.html b/src/main/resources/templates/auto-split-pdf.html
index 3e93c565..00b65c8d 100644
--- a/src/main/resources/templates/auto-split-pdf.html
+++ b/src/main/resources/templates/auto-split-pdf.html
@@ -1,6 +1,6 @@
 <!DOCTYPE html>
 <html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}"
-  xmlns:th="http://www.thymeleaf.org">
+  xmlns:th="https://www.thymeleaf.org">
 
 <head>
   <th:block th:insert="~{fragments/common :: head(title=#{autoSplitPDF.title}, header=#{autoSplitPDF.header})}">
diff --git a/src/main/resources/templates/change-creds.html b/src/main/resources/templates/change-creds.html
index adef8b55..ad366eb8 100644
--- a/src/main/resources/templates/change-creds.html
+++ b/src/main/resources/templates/change-creds.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{changeCreds.title}, header=#{changeCreds.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/book-to-pdf.html b/src/main/resources/templates/convert/book-to-pdf.html
index acd40b21..8d0f74cb 100644
--- a/src/main/resources/templates/convert/book-to-pdf.html
+++ b/src/main/resources/templates/convert/book-to-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{BookToPDF.title}, header=#{BookToPDF.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/file-to-pdf.html b/src/main/resources/templates/convert/file-to-pdf.html
index 1386a441..2230da33 100644
--- a/src/main/resources/templates/convert/file-to-pdf.html
+++ b/src/main/resources/templates/convert/file-to-pdf.html
@@ -1,6 +1,6 @@
 <!DOCTYPE html>
 <html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}"
-  xmlns:th="http://www.thymeleaf.org">
+  xmlns:th="https://www.thymeleaf.org">
 
 <head>
   <th:block th:insert="~{fragments/common :: head(title=#{fileToPDF.title}, header=#{fileToPDF.header})}"></th:block>
diff --git a/src/main/resources/templates/convert/html-to-pdf.html b/src/main/resources/templates/convert/html-to-pdf.html
index ff0bf143..54b2a3bc 100644
--- a/src/main/resources/templates/convert/html-to-pdf.html
+++ b/src/main/resources/templates/convert/html-to-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{HTMLToPDF.title}, header=#{HTMLToPDF.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/img-to-pdf.html b/src/main/resources/templates/convert/img-to-pdf.html
index 09d0461b..139ac8f8 100644
--- a/src/main/resources/templates/convert/img-to-pdf.html
+++ b/src/main/resources/templates/convert/img-to-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{imageToPDF.title}, header=#{imageToPDF.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/markdown-to-pdf.html b/src/main/resources/templates/convert/markdown-to-pdf.html
index af93f23c..97fa2c2d 100644
--- a/src/main/resources/templates/convert/markdown-to-pdf.html
+++ b/src/main/resources/templates/convert/markdown-to-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{MarkdownToPDF.title}, header=#{MarkdownToPDF.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-book.html b/src/main/resources/templates/convert/pdf-to-book.html
index 33fbd2e1..018adbc4 100644
--- a/src/main/resources/templates/convert/pdf-to-book.html
+++ b/src/main/resources/templates/convert/pdf-to-book.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{PDFToBook.title}, header=#{PDFToBook.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-csv.html b/src/main/resources/templates/convert/pdf-to-csv.html
index 23f804b0..6315c47b 100644
--- a/src/main/resources/templates/convert/pdf-to-csv.html
+++ b/src/main/resources/templates/convert/pdf-to-csv.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{PDFToCSV.title}, header=#{PDFToCSV.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-html.html b/src/main/resources/templates/convert/pdf-to-html.html
index 5006ad1b..6ac6e8f0 100644
--- a/src/main/resources/templates/convert/pdf-to-html.html
+++ b/src/main/resources/templates/convert/pdf-to-html.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{PDFToHTML.title}, header=#{PDFToHTML.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-img.html b/src/main/resources/templates/convert/pdf-to-img.html
index a0402fc1..0cf74dd0 100644
--- a/src/main/resources/templates/convert/pdf-to-img.html
+++ b/src/main/resources/templates/convert/pdf-to-img.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{pdfToImage.title}, header=#{pdfToImage.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-pdfa.html b/src/main/resources/templates/convert/pdf-to-pdfa.html
index 98f1565c..49257511 100644
--- a/src/main/resources/templates/convert/pdf-to-pdfa.html
+++ b/src/main/resources/templates/convert/pdf-to-pdfa.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{pdfToPDFA.title}, header=#{pdfToPDFA.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-presentation.html b/src/main/resources/templates/convert/pdf-to-presentation.html
index fcef6e65..bb6784de 100644
--- a/src/main/resources/templates/convert/pdf-to-presentation.html
+++ b/src/main/resources/templates/convert/pdf-to-presentation.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{PDFToPresentation.title}, header=#{PDFToPresentation.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-text.html b/src/main/resources/templates/convert/pdf-to-text.html
index e0fc5fbb..71865624 100644
--- a/src/main/resources/templates/convert/pdf-to-text.html
+++ b/src/main/resources/templates/convert/pdf-to-text.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{PDFToText.title}, header=#{PDFToText.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-word.html b/src/main/resources/templates/convert/pdf-to-word.html
index c17c2675..6ac90136 100644
--- a/src/main/resources/templates/convert/pdf-to-word.html
+++ b/src/main/resources/templates/convert/pdf-to-word.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{PDFToWord.title}, header=#{PDFToWord.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/pdf-to-xml.html b/src/main/resources/templates/convert/pdf-to-xml.html
index 8ee1237e..ce545ce0 100644
--- a/src/main/resources/templates/convert/pdf-to-xml.html
+++ b/src/main/resources/templates/convert/pdf-to-xml.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{PDFToXML.title}, header=#{PDFToXML.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/convert/url-to-pdf.html b/src/main/resources/templates/convert/url-to-pdf.html
index 03f26e9d..ee136b32 100644
--- a/src/main/resources/templates/convert/url-to-pdf.html
+++ b/src/main/resources/templates/convert/url-to-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{URLToPDF.title}, header=#{URLToPDF.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/crop.html b/src/main/resources/templates/crop.html
index fdb248fd..8f0ad935 100644
--- a/src/main/resources/templates/crop.html
+++ b/src/main/resources/templates/crop.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{crop.title}, header=#{crop.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/error.html b/src/main/resources/templates/error.html
index fd357afb..e24d114b 100644
--- a/src/main/resources/templates/error.html
+++ b/src/main/resources/templates/error.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{error.404.head})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/extract-page.html b/src/main/resources/templates/extract-page.html
index 05d171ce..1d054189 100644
--- a/src/main/resources/templates/extract-page.html
+++ b/src/main/resources/templates/extract-page.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{pageExtracter.title}, header=#{pageExtracter.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/home.html b/src/main/resources/templates/home.html
index 527df0fd..235363ab 100644
--- a/src/main/resources/templates/home.html
+++ b/src/main/resources/templates/home.html
@@ -1,6 +1,6 @@
 <!DOCTYPE html>
 <html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}"
-  xmlns:th="http://www.thymeleaf.org">
+  xmlns:th="https://www.thymeleaf.org">
 
 <head>
   <th:block th:insert="~{fragments/common :: head(title='')}"></th:block>
diff --git a/src/main/resources/templates/licenses.html b/src/main/resources/templates/licenses.html
index a2f81653..7754fe8c 100644
--- a/src/main/resources/templates/licenses.html
+++ b/src/main/resources/templates/licenses.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{licenses.title}, header=#{licenses.title})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/login.html b/src/main/resources/templates/login.html
index 1ddea9db..31bb4531 100644
--- a/src/main/resources/templates/login.html
+++ b/src/main/resources/templates/login.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{login.title}, header=#{login.header})}"></th:block>
     <link rel="stylesheet" href="css/login.css">
diff --git a/src/main/resources/templates/merge-pdfs.html b/src/main/resources/templates/merge-pdfs.html
index 62d95521..930c04c8 100644
--- a/src/main/resources/templates/merge-pdfs.html
+++ b/src/main/resources/templates/merge-pdfs.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{merge.title}, header=#{merge.header})}"></th:block>
     <link rel="stylesheet" href="css/merge.css">
diff --git a/src/main/resources/templates/misc/add-image.html b/src/main/resources/templates/misc/add-image.html
index 21ecfdc7..99837c96 100644
--- a/src/main/resources/templates/misc/add-image.html
+++ b/src/main/resources/templates/misc/add-image.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{addImage.title}, header=#{addImage.header})}"></th:block>
     <script src="js/thirdParty/interact.min.js"></script>
diff --git a/src/main/resources/templates/misc/add-page-numbers.html b/src/main/resources/templates/misc/add-page-numbers.html
index ea8281c8..4fbda6a9 100644
--- a/src/main/resources/templates/misc/add-page-numbers.html
+++ b/src/main/resources/templates/misc/add-page-numbers.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{addPageNumbers.title}, header=#{addPageNumbers.header})}"></th:block>
     <style>
diff --git a/src/main/resources/templates/misc/adjust-contrast.html b/src/main/resources/templates/misc/adjust-contrast.html
index b4811495..c758c39b 100644
--- a/src/main/resources/templates/misc/adjust-contrast.html
+++ b/src/main/resources/templates/misc/adjust-contrast.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{adjustContrast.title}, header=#{adjustContrast.header})}"></th:block>
     <style>
diff --git a/src/main/resources/templates/misc/auto-crop.html b/src/main/resources/templates/misc/auto-crop.html
index 6b6ffcdb..b5630cb7 100644
--- a/src/main/resources/templates/misc/auto-crop.html
+++ b/src/main/resources/templates/misc/auto-crop.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{autoCrop.title}, header=#{autoCrop.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/auto-rename.html b/src/main/resources/templates/misc/auto-rename.html
index 72bf41d0..025ed97c 100644
--- a/src/main/resources/templates/misc/auto-rename.html
+++ b/src/main/resources/templates/misc/auto-rename.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{auto-rename.title}, header=#{auto-rename.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/change-metadata.html b/src/main/resources/templates/misc/change-metadata.html
index 604ff0bc..8916287a 100644
--- a/src/main/resources/templates/misc/change-metadata.html
+++ b/src/main/resources/templates/misc/change-metadata.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{changeMetadata.title}, header=#{changeMetadata.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/compare.html b/src/main/resources/templates/misc/compare.html
index 93cbee58..ef27b43f 100644
--- a/src/main/resources/templates/misc/compare.html
+++ b/src/main/resources/templates/misc/compare.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{compare.title}, header=#{compare.header})}"></th:block>
     <style>
diff --git a/src/main/resources/templates/misc/compress-pdf.html b/src/main/resources/templates/misc/compress-pdf.html
index 093a09b5..cdb679d5 100644
--- a/src/main/resources/templates/misc/compress-pdf.html
+++ b/src/main/resources/templates/misc/compress-pdf.html
@@ -1,6 +1,6 @@
 <!DOCTYPE html>
 <html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}"
-  xmlns:th="http://www.thymeleaf.org">
+  xmlns:th="https://www.thymeleaf.org">
 
 <head>
   <th:block th:insert="~{fragments/common :: head(title=#{compress.title}, header=#{compress.header})}"></th:block>
diff --git a/src/main/resources/templates/misc/extract-image-scans.html b/src/main/resources/templates/misc/extract-image-scans.html
index a49df7cb..4ae50678 100644
--- a/src/main/resources/templates/misc/extract-image-scans.html
+++ b/src/main/resources/templates/misc/extract-image-scans.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{home.ScannerImageSplit.title}, header=#{home.ScannerImageSplit.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/extract-images.html b/src/main/resources/templates/misc/extract-images.html
index 71cc686f..8442b46b 100644
--- a/src/main/resources/templates/misc/extract-images.html
+++ b/src/main/resources/templates/misc/extract-images.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{extractImages.title}, header=#{extractImages.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/fake-scan.html b/src/main/resources/templates/misc/fake-scan.html
index 97d681a1..5de49969 100644
--- a/src/main/resources/templates/misc/fake-scan.html
+++ b/src/main/resources/templates/misc/fake-scan.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{fakeScan.title}, header=#{fakeScan.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/flatten.html b/src/main/resources/templates/misc/flatten.html
index 120f6f40..2883cd57 100644
--- a/src/main/resources/templates/misc/flatten.html
+++ b/src/main/resources/templates/misc/flatten.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{flatten.title}, header=#{flatten.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/ocr-pdf.html b/src/main/resources/templates/misc/ocr-pdf.html
index df99b969..a74242ae 100644
--- a/src/main/resources/templates/misc/ocr-pdf.html
+++ b/src/main/resources/templates/misc/ocr-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{ocr.title}, header=#{ocr.header})}"></th:block>
     <script>
diff --git a/src/main/resources/templates/misc/print-file.html b/src/main/resources/templates/misc/print-file.html
index 056d7328..16dc5c3f 100644
--- a/src/main/resources/templates/misc/print-file.html
+++ b/src/main/resources/templates/misc/print-file.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{printFile.title}, header=#{printFile.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/remove-annotations.html b/src/main/resources/templates/misc/remove-annotations.html
index c928d1c0..5d0d8219 100644
--- a/src/main/resources/templates/misc/remove-annotations.html
+++ b/src/main/resources/templates/misc/remove-annotations.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{removeAnnotations.title}, header=#{removeAnnotations.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/remove-blanks.html b/src/main/resources/templates/misc/remove-blanks.html
index f313cea5..7abee689 100644
--- a/src/main/resources/templates/misc/remove-blanks.html
+++ b/src/main/resources/templates/misc/remove-blanks.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{removeBlanks.title}, header=#{removeBlanks.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/repair.html b/src/main/resources/templates/misc/repair.html
index 001332ee..76f3a6cb 100644
--- a/src/main/resources/templates/misc/repair.html
+++ b/src/main/resources/templates/misc/repair.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{repair.title}, header=#{repair.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/misc/show-javascript.html b/src/main/resources/templates/misc/show-javascript.html
index 6e643f36..b582ab1e 100644
--- a/src/main/resources/templates/misc/show-javascript.html
+++ b/src/main/resources/templates/misc/show-javascript.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{showJS.title}, header=#{showJS.header})}"></th:block>
     <link href="css/prism.css" rel="stylesheet">
diff --git a/src/main/resources/templates/misc/stamp.html b/src/main/resources/templates/misc/stamp.html
index 3f882c96..d75eb0f9 100644
--- a/src/main/resources/templates/misc/stamp.html
+++ b/src/main/resources/templates/misc/stamp.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{AddStampRequest.title}, header=#{AddStampRequest.header})}"></th:block>
     <style>
diff --git a/src/main/resources/templates/multi-page-layout.html b/src/main/resources/templates/multi-page-layout.html
index dc0a0b9c..313329b4 100644
--- a/src/main/resources/templates/multi-page-layout.html
+++ b/src/main/resources/templates/multi-page-layout.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{pageLayout.title}, header=#{pageLayout.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/multi-tool.html b/src/main/resources/templates/multi-tool.html
index 92b4537f..b578d594 100644
--- a/src/main/resources/templates/multi-tool.html
+++ b/src/main/resources/templates/multi-tool.html
@@ -1,6 +1,6 @@
 <!DOCTYPE html>
 <html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}"
-  xmlns:th="http://www.thymeleaf.org">
+  xmlns:th="https://www.thymeleaf.org">
 
 <head>
   <th:block th:insert="~{fragments/common :: head(title=#{multiTool.title}, header=#{multiTool.header})}"></th:block>
diff --git a/src/main/resources/templates/overlay-pdf.html b/src/main/resources/templates/overlay-pdf.html
index c427dacb..0e48a101 100644
--- a/src/main/resources/templates/overlay-pdf.html
+++ b/src/main/resources/templates/overlay-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{split-by-size-or-count.title}, header=#{split-by-size-or-count.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/pdf-organizer.html b/src/main/resources/templates/pdf-organizer.html
index 7083f0f8..85b4acab 100644
--- a/src/main/resources/templates/pdf-organizer.html
+++ b/src/main/resources/templates/pdf-organizer.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{pdfOrganiser.title}, header=#{pdfOrganiser.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/pdf-to-single-page.html b/src/main/resources/templates/pdf-to-single-page.html
index 28946d05..3590bc35 100644
--- a/src/main/resources/templates/pdf-to-single-page.html
+++ b/src/main/resources/templates/pdf-to-single-page.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{pdfToSinglePage.title}, header=#{pdfToSinglePage.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/pipeline.html b/src/main/resources/templates/pipeline.html
index 991aef18..179cab75 100644
--- a/src/main/resources/templates/pipeline.html
+++ b/src/main/resources/templates/pipeline.html
@@ -3,7 +3,7 @@
   th:lang="${#locale.language}"
   th:dir="#{language.direction}"
   th:data-language="${#locale.toString()}"
-  xmlns:th="http://www.thymeleaf.org"
+  xmlns:th="https://www.thymeleaf.org"
 >
   <head>
     <th:block
diff --git a/src/main/resources/templates/remove-pages.html b/src/main/resources/templates/remove-pages.html
index 93357b57..e89a484f 100644
--- a/src/main/resources/templates/remove-pages.html
+++ b/src/main/resources/templates/remove-pages.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{pageRemover.title}, header=#{pageRemover.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/rotate-pdf.html b/src/main/resources/templates/rotate-pdf.html
index 386ebe72..7b428018 100644
--- a/src/main/resources/templates/rotate-pdf.html
+++ b/src/main/resources/templates/rotate-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{rotate.title}, header=#{rotate.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/scale-pages.html b/src/main/resources/templates/scale-pages.html
index a9bc7e86..366cea2c 100644
--- a/src/main/resources/templates/scale-pages.html
+++ b/src/main/resources/templates/scale-pages.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{scalePages.title}, header=#{scalePages.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/add-password.html b/src/main/resources/templates/security/add-password.html
index c1283173..992a0df2 100644
--- a/src/main/resources/templates/security/add-password.html
+++ b/src/main/resources/templates/security/add-password.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{addPassword.title}, header=#{addPassword.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/add-watermark.html b/src/main/resources/templates/security/add-watermark.html
index 6f0bdb5f..12e706e4 100644
--- a/src/main/resources/templates/security/add-watermark.html
+++ b/src/main/resources/templates/security/add-watermark.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{watermark.title}, header=#{watermark.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/auto-redact.html b/src/main/resources/templates/security/auto-redact.html
index c92f7e9f..7709af87 100644
--- a/src/main/resources/templates/security/auto-redact.html
+++ b/src/main/resources/templates/security/auto-redact.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{autoRedact.title}, header=#{autoRedact.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/cert-sign.html b/src/main/resources/templates/security/cert-sign.html
index 0d084906..8cd1aa3d 100644
--- a/src/main/resources/templates/security/cert-sign.html
+++ b/src/main/resources/templates/security/cert-sign.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{certSign.title}, header=#{certSign.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/change-permissions.html b/src/main/resources/templates/security/change-permissions.html
index 335ebc32..18af4cdf 100644
--- a/src/main/resources/templates/security/change-permissions.html
+++ b/src/main/resources/templates/security/change-permissions.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{permissions.title}, header=#{permissions.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/get-info-on-pdf.html b/src/main/resources/templates/security/get-info-on-pdf.html
index ad6d297b..1953a1bf 100644
--- a/src/main/resources/templates/security/get-info-on-pdf.html
+++ b/src/main/resources/templates/security/get-info-on-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{getPdfInfo.title}, header=#{getPdfInfo.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/remove-password.html b/src/main/resources/templates/security/remove-password.html
index 1cdf7247..d78269ca 100644
--- a/src/main/resources/templates/security/remove-password.html
+++ b/src/main/resources/templates/security/remove-password.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{removePassword.title}, header=#{removePassword.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/remove-watermark.html b/src/main/resources/templates/security/remove-watermark.html
index 0e275060..1bba11c6 100644
--- a/src/main/resources/templates/security/remove-watermark.html
+++ b/src/main/resources/templates/security/remove-watermark.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{remove-watermark.title}, header=#{remove-watermark.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/security/sanitize-pdf.html b/src/main/resources/templates/security/sanitize-pdf.html
index 3103c744..b4077b9b 100644
--- a/src/main/resources/templates/security/sanitize-pdf.html
+++ b/src/main/resources/templates/security/sanitize-pdf.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{sanitizePDF.title}, header=#{sanitizePDF.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/sign.html b/src/main/resources/templates/sign.html
index 7b6347e2..a68c02d9 100644
--- a/src/main/resources/templates/sign.html
+++ b/src/main/resources/templates/sign.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{sign.title}, header=#{sign.header})}"></th:block>
     <link rel="stylesheet" href="css/sign.css">
diff --git a/src/main/resources/templates/split-by-size-or-count.html b/src/main/resources/templates/split-by-size-or-count.html
index f92a7380..deb9fa84 100644
--- a/src/main/resources/templates/split-by-size-or-count.html
+++ b/src/main/resources/templates/split-by-size-or-count.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{split-by-size-or-count.title}, header=#{split-by-size-or-count.header})}"></th:block>
   </head>
diff --git a/src/main/resources/templates/split-pdf-by-sections.html b/src/main/resources/templates/split-pdf-by-sections.html
index 9790b1b2..2268aadc 100644
--- a/src/main/resources/templates/split-pdf-by-sections.html
+++ b/src/main/resources/templates/split-pdf-by-sections.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="http://www.thymeleaf.org">
+<html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}" xmlns:th="https://www.thymeleaf.org">
   <head>
   <th:block th:insert="~{fragments/common :: head(title=#{split-by-sections.title}, header=#{split-by-sections.header})}"></th:block>
     <link rel="stylesheet" href="css/split-pdf-by-sections.css">
diff --git a/src/main/resources/templates/split-pdfs.html b/src/main/resources/templates/split-pdfs.html
index 9146cdf7..2491dbde 100644
--- a/src/main/resources/templates/split-pdfs.html
+++ b/src/main/resources/templates/split-pdfs.html
@@ -1,6 +1,6 @@
 <!DOCTYPE html>
 <html th:lang="${#locale.language}" th:dir="#{language.direction}" th:data-language="${#locale.toString()}"
-  xmlns:th="http://www.thymeleaf.org">
+  xmlns:th="https://www.thymeleaf.org">
 
 <head>
   <th:block th:insert="~{fragments/common :: head(title=#{split.title}, header=#{split.header})}"></th:block>
