diff --git a/public/js/index.js b/public/js/index.js
index 22ac9633c..eca9aef47 100644
--- a/public/js/index.js
+++ b/public/js/index.js
@@ -2255,8 +2255,6 @@ function setDeadline() {
 }
 
 function updateDeadline(deadlineString) {
-    var issue_api_url = suburl + '/api/v1/repos/' + $('meta[name=_repo_owner]').attr("content") + '/' + $('meta[name=_repo_name]').attr("content") + '/issues/' + $('meta[name=_issue_index]').attr("content");
-
     $('#deadline-loader').addClass('loading');
 
     var realDeadline = null;
@@ -2264,7 +2262,7 @@ function updateDeadline(deadlineString) {
         realDeadline = deadlineString + 'T13:55:29.764Z';
     }
 
-    $.ajax(issue_api_url + '/deadline', {
+    $.ajax($('#update-issue-deadline-form').attr('action') + '/deadline', {
         data: JSON.stringify({
             'due_date': realDeadline,
         }),
diff --git a/templates/base/head.tmpl b/templates/base/head.tmpl
index 14752e265..a486d9b9b 100644
--- a/templates/base/head.tmpl
+++ b/templates/base/head.tmpl
@@ -21,13 +21,6 @@
 	{{if .SearchLimit}}
 		<meta name="_search_limit" content="{{.SearchLimit}}" />
 	{{end}}
-	{{with .Repository}}
-		<meta name="_repo_owner" content="{{.Owner.Name}}" />
-		<meta name="_repo_name" content="{{.Name}}" />
-	{{end}}
-	{{with .Issue}}
-		<meta name="_issue_index" content="{{.Index}}" />
-	{{end}}
 {{if .GoGetImport}}
 	<meta name="go-import" content="{{.GoGetImport}} git {{.CloneLink.HTTPS}}">
 	<meta name="go-source" content="{{.GoGetImport}} _ {{.GoDocDirectory}} {{.GoDocFile}}">
diff --git a/templates/repo/issue/view_content/sidebar.tmpl b/templates/repo/issue/view_content/sidebar.tmpl
index 4cf095f6c..2375fc208 100644
--- a/templates/repo/issue/view_content/sidebar.tmpl
+++ b/templates/repo/issue/view_content/sidebar.tmpl
@@ -230,15 +230,17 @@
 		{{end}}
 
 		{{if and .IsSigned .IsRepositoryWriter}}
-			<div class="ui fluid action input"{{if gt .Issue.DeadlineUnix 0}} style="display: none;"{{end}} id="deadlineForm">
-				<input required placeholder="{{.i18n.Tr "repo.issues.due_date_form"}}" {{if gt .Issue.DeadlineUnix 0}}value="{{.Issue.DeadlineUnix.Format "2006-01-02"}}"{{end}} type="date" name="deadlineDate" id="deadlineDate" style="min-width: 13.8rem;border-radius: 4px 0 0 4px;border-right: 0;white-space: nowrap;">
-				<button class="ui green icon button" onclick="setDeadline();">
-				{{if gt .Issue.DeadlineUnix 0}}
-					<i class="edit icon"></i>
-				{{else}}
-					<i class="plus icon"></i>
-				{{end}}
-				</button>
+			<div {{if gt .Issue.DeadlineUnix 0}} style="display: none;"{{end}} id="deadlineForm">
+				<form class="ui fluid action input" action="{{AppSubUrl}}/api/v1/repos/{{.Repository.Owner.Name}}/{{.Repository.Name}}/issues/{{.Issue.Index}}" method="post" id="update-issue-deadline-form" onsubmit="setDeadline();return false;">
+					<input required placeholder="{{.i18n.Tr "repo.issues.due_date_form"}}" {{if gt .Issue.DeadlineUnix 0}}value="{{.Issue.DeadlineUnix.Format "2006-01-02"}}"{{end}} type="date" name="deadlineDate" id="deadlineDate" style="width: 12.8rem;border-radius: 4px 0 0 4px;border-right: 0;white-space: nowrap;">
+					<button class="ui green icon button">
+					{{if gt .Issue.DeadlineUnix 0}}
+						<i class="edit icon"></i>
+					{{else}}
+						<i class="plus icon"></i>
+					{{end}}
+					</button>
+				</form>
 			</div>
 		{{end}}
 		</div>