Met with empty schemas page after docker-compose upgrade

[pavish]

Description

• Performed a guided install of 0.1.3
  • It connects a single external user DB with 2 schemas and multiple tables.
• Upgraded to 0.1.4 following the information in the latest docs (from Update Installation Documentation for Release 0.1.4 #3227).
  • Moved Postgres volumes as mentioned in docs.
• Upgrade succeeded.
• Met with the following page:
  
• I repeated the upgrade twice and this happened both times.
• The database name, host, and port of the user database connection were empty.
  

[mathemancer]

@pavish Can you give me a little detail about whether you started with MATHESAR_DATABASES (I assume yes), whether you removed it, and when you removed it?

[pavish]

@mathemancer I did not remove it.

• I followed the guided install script which installed Mathesar and set up the MATHESAR_DATABASES env variable.
  • I chose 'use existing' instead of 'create new' in the guided install DB prompt, and gave the credentials to an existing database.
• I started Mathesar, it worked fine.
• I then following the upgrade instructions as per the docs, and met with this error.