Add 10.12.15 RN

Author: MariaShaposhnikova

content/en/docs/releasenotes/studio-pro/10/10.12.md

@@ -10,6 +10,19 @@ mts: true
 This is the [MTS](/releasenotes/studio-pro/lts-mts/#mts) version 10 release for apps in production.
 {{% /alert %}}
 
+## 10.12.15 {#101215}
+
+**Release date: February 28, 2025**
+
+{{% button color="info" href="https://marketplace.mendix.com/link/studiopro/10.12.15" text="Go to Marketplace" title="Download version 10.12.15 from the Marketplace" %}}
+
+### Fixes
+
+- We decreased the chance for database transaction deadlocks when updating the **LastActive** attribute for System.Session instances. (Ticket 240094)
+
+- We fixed an issue where attempting to convert nanoflow or microflow in the System module resulted in an error. This option is now disabled for the System module.
+- We fixed an issue with updating module roles in the **Module Security** dialog box that occurred after moving a document between modules.
+
 ## 10.12.14 {#101214}
 
 **Release date: February 13, 2025**