Hey there, thanks for reaching out and welcome to the Streamlit community! 
You’re absolutely right—this is a known issue that pops up when the Debian security repository’s Release file expires or its codename changes (e.g., from bullseye-security to bookworm-security). This causes apt-get installs (like your libgl1 via packages.txt) to fail, blocking system dependencies for all apps on Streamlit Community Cloud.
Unfortunately, as an app developer, you can’t directly update or fix the Debian repositories used by Streamlit Community Cloud. This is a platform-level issue that only the Streamlit team can resolve. The best workaround is to wait for the Streamlit team to refresh or update the base containers, which they typically do quickly when these repo issues arise. Deleting and redeploying the app or rebooting sometimes helps after the fix is deployed, but not before. For more details and community updates, see this forum thread and Streamlit’s official docs.
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