Document Debian 13 TAR header warnings in .NET 10.0 known issues

[Copilot]

.NET 10.0 packages for Debian 13 (Trixie) install successfully but emit W: Unknown TAR header type 120 warnings during installation. This documents the cosmetic nature of these warnings.

Changes

• Added "Debian 13 packages work but display TAR header warnings" section to release-notes/10.0/known-issues.md
• Clarified that warnings are cosmetic and don't affect SDK/runtime functionality
• Referenced Microsoft's Debian installation documentation

Example installation output showing the warnings:

W: Unknown TAR header type 120
W: Unknown TAR header type 120
...

The packages install and function correctly despite these warnings. Fix is in progress.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• api0.prismacloud.io
  • Triggering command: /usr/bin/python3 /home/REDACTED/.local/bin/checkov --config-file .checkov.yml --directory . --quiet (dns block)
• learn.microsoft.com
  • Triggering command: node /home/REDACTED/work/core/core/node_modules/.bin/markdown-link-check --config .github/workflows/markdown-link-check-config.json release-notes/10.0/known-issues.md (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

Please update the 10.0 known issues file. We need to capture that 10.0 packages for Debian 13 work but exhibit a warning that we are in the process of fixing.

Instructions: https://learn.microsoft.com/dotnet/core/install/linux-debian

Example usage (from a few minutes ago, in a container):

root@ddb74e5d9b19:/# apt update && apt install -y dotnet-sdk-10.0
Hit:1 http://deb.debian.org/debian trixie InRelease
Hit:2 http://deb.debian.org/debian trixie-updates InRelease
Hit:3 http://deb.debian.org/debian-security trixie-security InRelease
Get:4 https://packages.microsoft.com/debian/13/prod trixie InRelease [3952 B]
Get:5 https://packages.microsoft.com/debian/13/prod trixie/main armhf Packages [439 B]
Get:6 https://packages.microsoft.com/debian/13/prod trixie/main arm64 Packages [1700 B]
Get:7 https://packages.microsoft.com/debian/13/prod trixie/main all Packages [342 B]
Get:8 https://packages.microsoft.com/debian/13/prod trixie/main amd64 Packages [3573 B]
Fetched 10.0 kB in 1s (14.4 kB/s)
All packages are up to date.
Installing:
dotnet-sdk-10.0

Installing dependencies:
aspnetcore-runtime-10.0 dotnet-hostfxr-10.0 krb5-locales libk5crypto3
aspnetcore-targeting-pack-10.0 dotnet-runtime-10.0 libcom-err2 libkeyutils1
dotnet-apphost-pack-10.0 dotnet-runtime-deps-10.0 libgssapi-krb5-2 libkrb5-3
dotnet-host dotnet-targeting-pack-10.0 libicu76 libkrb5support0

Suggested packages:
krb5-doc krb5-user

Summary:
Upgrading: 0, Installing: 17, Removing: 0, Not Upgrading: 0
Download size: 250 MB
Space needed: 652 GB / 685 GB available

Get:1 http://deb.debian.org/debian trixie/main amd64 libkrb5support0 amd64 1.21.3-5 [33.0 kB]
Get:2 http://deb.debian.org/debian trixie/main amd64 libcom-err2 amd64 1.47.2-3+b3 [25.0 kB]
Get:3 http://deb.debian.org/debian trixie/main amd64 libk5crypto3 amd64 1.21.3-5 [81.5 kB]
Get:4 http://deb.debian.org/debian trixie/main amd64 libkeyutils1 amd64 1.6.3-6 [9456 B]
Get:5 http://deb.debian.org/debian trixie/main amd64 libkrb5-3 amd64 1.21.3-5 [326 kB]
Get:6 https://packages.microsoft.com/debian/13/prod trixie/main amd64 dotnet-host amd64 10.0.0 [43.9 kB]
Get:7 https://packages.microsoft.com/debian/13/prod trixie/main amd64 dotnet-hostfxr-10.0 amd64 10.0.0 [149 kB]
Get:8 https://packages.microsoft.com/debian/13/prod trixie/main amd64 dotnet-runtime-deps-10.0 amd64 10.0.0 [3218 B]
Get:9 https://packages.microsoft.com/debian/13/prod trixie/main amd64 dotnet-runtime-10.0 amd64 10.0.0 [36.5 MB]
Get:10 http://deb.debian.org/debian trixie/main amd64 libgssapi-krb5-2 amd64 1.21.3-5 [138 kB]
Get:11 http://deb.debian.org/debian trixie/main amd64 libicu76 amd64 76.1-4 [9722 kB]
Get:12 https://packages.microsoft.com/debian/13/prod trixie/main amd64 aspnetcore-runtime-10.0 amd64 10.0.0 [12.8 MB]
Get:13 http://deb.debian.org/debian trixie/main amd64 krb5-locales all 1.21.3-5 [101 kB]
Get:14 https://packages.microsoft.com/debian/13/prod trixie/main amd64 dotnet-targeting-pack-10.0 amd64 10.0.0 [6686 kB]
Get:15 https://packages.microsoft.com/debian/13/prod trixie/main amd64 aspnetcore-targeting-pack-10.0 amd64 10.0.0 [6915 kB]
Get:16 https://packages.microsoft.com/debian/13/prod trixie/main amd64 dotnet-apphost-pack-10.0 amd64 10.0.0 [5376 kB]
Get:17 https://packages.microsoft.com/debian/13/prod trixie/main amd64 dotnet-sdk-10.0 amd64 10.0.100 [171 MB]
Fetched 250 MB in 16s (15.6 MB/s)
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 79, line 17.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @inc (you may need to install the Term::ReadLine module) (@inc entries checked: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.40.1 /usr/local/share/perl/5.40.1 /usr/lib/x86_64-linux-gnu/perl5/5.40 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl-base /usr/lib/x86_64-linux-gnu/perl/5.40 /usr/share/perl/5.40 /usr/local/lib/site_perl) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 8, line 17.)
debconf: falling back to frontend: Teletype
W: Unknown TAR header type 120
W: Unknown TAR header type 120
W: Unknown TAR header type 120
W: Unknown TAR header type 120
W: Unknown TAR header type 120
W: Unknown TAR header type 120
W: Unknown TAR header type 120
W: Unknown TAR header type 120
W: Unknown TAR header type 120
W: Unknown TAR header type 120

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