AdGuard does not recognise "tcp://" as a valid DNS server protocol

[DandelionSprout]

Please answer the following questions for yourself before submitting an issue.

• I am running the latest version
• I checked the documentation and found no answer
• I checked to make sure that this issue has not already been filed

AdGuard version

v4.0 Beta 1

Environment

- OS: Android 10
- Device: Motorola One Zoom
- Firmware: Official

Root access

• Yes, I have it.

What filters do you have enabled?

AdGuard Base filter, AdGuard Mobile Ads filter, EasyList Lithuania, Adblock List for Finland, Dandelion Sprout's Annoyances List, IndianList

What Stealth Mode options do you have enabled?

No response

Issue Details

Steps to reproduce:

1. Go to Protection → DNS Protection → DNS server → Custom servers → Add DNS server → In "Server addresses, one per line", type in something like tcp://192.1.2.3 → Try to press "Save".
2. The error message "Please enter a valid protocol" shows up.

Using tcp:// for a DNS server is supported in AdGuard Home, and was supported in AdGuard for Android 3.x, so there seems to have been a feature regression that has occured.

Expected Behavior

Specifying and using the tcp:// protocol for a custom DNS server, is supported.

Actual Behavior

The app does not seem to allow server addresses that specify the tcp:// protocol

Screenshots

Screenshot 1:

Additional Information

Although very few professionally run DNS servers seem to officially support tcp:// (although AdGuard Home supports it by default), I figure that since it's supported in other/earlier AdGuard products, then it would've been great to see it be supported in AdGuard for Android 4.x as well.

[Versty]

@DandelionSprout Thank you for reporting.
This issue had dropped out of our radar, but now we have successfully reproduced the problem.
Will do our best to restore the functionality.

[artemiv4nov]

Well, please use a plain DNS server add without "tcp://" and your DNS server will be added then.

[DandelionSprout]

It was supported in 3.x, it is still supported in AdGuard Home, so please don't try to do this kind of belittling passive-aggression on me.

I am definitely @-ing @ameshkov for a Second Opinion on this.

[ameshkov]

@DandelionSprout it's actually controlled by DnsLibs, opened a feature request there: AdguardTeam/DnsLibs#208

[artemiv4nov]

@DandelionSprout Please follow rules and subscribe to another feature request.