fix: Toolbar Types crash and multilingual redirects (backport)

[pratyush07-hub]

Backport PR

This is a backport of PR #7637 to the 18.x.x branch.

Description

This PR fixes the issue by :

• The crash happened because the code assumed langmap[lang] always exists.
• Now, if a language is not in langmap, it will fall back to displaying the language code itself, preventing the toolbar from crashing.

Changelog:

• Added a news file documenting this bug fix.

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