:+1: version and update docs

CHANGES.md

@@ -1,6 +1,12 @@
 # CHANGES
 
-## v4.2.0-RC
+
+## v4.2.1-RC
+
+* Fix: Consecutive save operations with HackMD fail
+* Fix: Switching theme to kibela fail
+
+## v4.2.0
 
 ### BREAKING CHANGES
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "growi",
-  "version": "4.2.0-RC",
+  "version": "4.2.1-RC",
   "description": "Team collaboration software using markdown",
   "tags": [
     "wiki",