diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4d82fe30d..6db54f74c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,39 @@
+# [1.21.3](https://github.com/gotson/komga/compare/1.21.2...1.21.3) (2025-05-16)
+## 🐛 Fixes
+**webui**
+- add missing characters for Japanese series grouping ([0a2c3ac](https://github.com/gotson/komga/commits/0a2c3ac)), closes [#1959](https://github.com/gotson/komga/issues/1959)
+- webtoon page margin is not restored ([80fa75a](https://github.com/gotson/komga/commits/80fa75a)), closes [#1944](https://github.com/gotson/komga/issues/1944)
+
+**unscoped**
+- epubs would have a "null" comment in the Media ([343add1](https://github.com/gotson/komga/commits/343add1))
+
+## 🔄️ Changes
+
+- remove startup task to fix missing thumbnail metadata ([a568a7d](https://github.com/gotson/komga/commits/a568a7d))
+- rename REST controller operations for better clarity in generated openapi spec ([95afb4b](https://github.com/gotson/komga/commits/95afb4b))
+
+## 🛠  Build
+**conveyor**
+- update conveyor compatibility to 18 ([2120edb](https://github.com/gotson/komga/commits/2120edb))
+
+**webui**
+- update Browserslist db ([e0a8edf](https://github.com/gotson/komga/commits/e0a8edf))
+- update Browserslist db (#1926) ([9ae39c0](https://github.com/gotson/komga/commits/9ae39c0)), closes [#1926](https://github.com/gotson/komga/issues/1926)
+
+## 📝 Documentation
+**api**
+- better operationId ([f03ba84](https://github.com/gotson/komga/commits/f03ba84))
+
+## ⚙️ Dependencies
+**ci**
+- bump hydraulic-software/conveyor from 17.0 to 18.0 ([ec7d4e3](https://github.com/gotson/komga/commits/ec7d4e3))
+- bump peter-evans/dockerhub-description from 4.0.0 to 4.0.2 ([08941f0](https://github.com/gotson/komga/commits/08941f0))
+
+**webui**
+- bump http-proxy-middleware in /komga-webui ([6c486c0](https://github.com/gotson/komga/commits/6c486c0))
+- bump @babel/helpers from 7.22.15 to 7.27.0 in /komga-webui ([c618047](https://github.com/gotson/komga/commits/c618047))
+- bump @babel/runtime from 7.22.15 to 7.27.0 in /komga-webui ([77c8aa5](https://github.com/gotson/komga/commits/77c8aa5))
+
 # [1.21.2](https://github.com/gotson/komga/compare/1.21.1...1.21.2) (2025-03-12)
 ## 🐛 Fixes
 **conveyor**
diff --git a/gradle.properties b/gradle.properties
index ad0bd5893..23b83dc9f 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,2 +1,2 @@
-version=1.21.2
+version=1.21.3
 org.gradle.jvmargs=-Xmx2G
diff --git a/komga/docs/openapi.json b/komga/docs/openapi.json
index 0248ff1e5..f00c15c4c 100644
--- a/komga/docs/openapi.json
+++ b/komga/docs/openapi.json
@@ -7,7 +7,7 @@
       "url": "https://github.com/gotson/komga/blob/master/LICENSE"
     },
     "title": "Komga API",
-    "version": "1.21.2"
+    "version": "1.21.3"
   },
   "externalDocs": {
     "description": "Komga documentation",
@@ -23,11 +23,11 @@
       "description": "Local development server",
       "variables": {
         "port": {
-          "default": "25600",
           "enum": [
             "8080",
             "25600"
-          ]
+          ],
+          "default": "25600"
         }
       }
     }
@@ -10394,9 +10394,6 @@
                   "negative": {
                     "type": "boolean"
                   },
-                  "positive": {
-                    "type": "boolean"
-                  },
                   "seconds": {
                     "type": "integer",
                     "format": "int64"
@@ -10495,9 +10492,6 @@
                   "negative": {
                     "type": "boolean"
                   },
-                  "positive": {
-                    "type": "boolean"
-                  },
                   "seconds": {
                     "type": "integer",
                     "format": "int64"
@@ -14309,4 +14303,4 @@
       ]
     }
   ]
-}
+}
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