Broken pipe error immediatly after opening a new session

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• iTerm2 version: 3.4.0beta4
• OS version: 10.15.4 (19E266)
• com.googlecode.iterm2.plist
• debuglog.txt

Detailed steps to reproduce the problem:

1. Open a new session
2. See "Session ended (broken pipe)" banner

Some other data:

• I've tried changing the shell to bash but still get the same error
• Terminal works fine
• I've checked that I have the default shell set to Login shell
• Tried setting zsh directly as shell
• Removed all of my zsh config files to discard an issue with plugins or configs
• I still have some working sessions and I tried running zsh inside them and it works fine there