update description

Author: Maksim Sadym

roadmap.md

@@ -91,9 +91,9 @@ This scenario loads a web page and prints it as a PDF. In spec terms, this invol
 - [x] Some items from the previous milestones
 - [x] [Printing to PDF as Base64-encoded string](https://w3c.github.io/webdriver-bidi/#command-browsingContext-print)
 
-### Incognito mode
+### Private browsing mode
 
-This scenario creates a session with browser in incognito mode. In spec terms, this involves:
+This scenario initiates a browsing session in "private browsing" mode, ensuring that no noticeable side effects result from the creation of such a session. In spec terms, this involves:
 
 - [x] Some items from the previous milestones
 - [ ] Create session with isolation and deleting of cookies, site data, and browsing history.