DoH with h3:// scheme works unstable, https:// works fine

[ammnt]

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• [X] Filters were updated before reproducing an issue
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AdGuard version

7.18.1 (4778) (CL 1.15.55, DL 2.5.33 )

Browser version

Firefox 131.0 (64-разрядный)

OS version

Windows 11 23H2

Issue Details

Steps to reproduce:

1. Install AdGuard for Windows
2. Install AdGuard VPN for Windows
3. Add your own DoH server with h3:// scheme
4. Test it

Expected Behavior

DNS resolving will be more stable and faster

Actual Behavior

DNS resolving is unstable. SERVFAIL error in logs etc.

Screenshots

Screenshot 1


Additional Information

Verbose logs from app and VPN + exported settings will be sent to devteam@adguard.com

[ammnt]

Logs has been sent just now. Support ticket: 964926.

[ammnt]

Same behavior with android applications.