Linux Installation Guide Contains Invalid Repo URL and Lacks DEB822 Format Support

[junzhang-bjtu]

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• [ ✅] Searched http://support.typora.io/

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Describe the bug
The Linux installation instructions on https://typoraio.cn/#linux contain two issues:

1. A typo in the repository URL: https:/typoraio.cn/linux is missing one slash (/), should be https://typoraio.cn/linux.
2. The instructions use the legacy sources.list format, but modern Debian/Ubuntu systems recommend the DEB822 format (.sources files) for better clarity and maintainability.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'https://typoraio.cn/#linux'
2. Copy the provided installation commands
3. Run the command:
   echo "deb [signed-by=/etc/apt/keyrings/typora.gpg] https:/typoraio.cn/linux ./" | sudo tee /etc/apt/sources.list.d/typora.list
4. See error: apt update fails

Expected behavior
The installation instructions should:

• Use a correct and valid repository URL (https://...)
• Prefer the modern DEB822 format (e.g., /etc/apt/sources.list.d/typora.sources) as recommended by Debian and Ubuntu documentation.

Screenshots / Screencasts

To Fix

# Create the keyrings directory (if it does not exist)
sudo mkdir -p /etc/apt/keyrings

# Download and save the GPG key
curl -fsSL https://typoraio.cn/linux/typora.gpg | sudo gpg --dearmor -o /etc/apt/keyrings/typora.gpg

# Add a software source in DEB822 format
cat <<EOF | sudo tee /etc/apt/sources.list.d/typora.sources
Types: deb
URIs: https://typoraio.cn/linux
Suites: ./
Signed-By: /etc/apt/keyrings/typora.gpg
EOF

# Update and Install
sudo apt update
sudo apt install typora