Update extensions.md

Author: puglieri

docs/general/extensions.md

@@ -59,7 +59,11 @@ Its source code is [available on GitHub](https://github.com/Rob--W/dont-track-me
 
 SponsorBlock skips sponsored segments in YouTube videos. It saves time by jumping straight to the main content and removes interruptions from ads and self-promotions.
 
-> This userscript runs exclusively on our desktop applications, AdGuard for Windows and AdGuard for Mac.
+:::warning
+
+This userscript runs exclusively on our desktop applications, AdGuard for Windows and AdGuard for Mac.
+
+:::
 
 To try it out: