[FAQ Bot] NEW: GitHub Codespaces: pgAdmin in Docker shows a blank screen after login

_questions/machine-learning-zoomcamp/misc/037_eed362d5db_github-codespaces-pgadmin-docker.md

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+id: eed362d5db
+question: 'GitHub Codespaces: pgAdmin in Docker shows a blank screen after login'
+sort_order: 37
+---
+
+Running pgAdmin in Docker behind GitHub Codespaces reverse proxy can result in a blank screen after logging in. This is typically due to session or proxy issues when running behind Codespaces’ reverse proxy. Resolve with two options:
+
+Option 1: Set the following environment variables to configure the proxy handling:
+
+- `PGADMIN_CONFIG_PROXY_X_HOST_COUNT`: 1
+- `PGADMIN_CONFIG_PROXY_X_PREFIX_COUNT`: 1
+
+This allows pgAdmin to work properly with Codespaces’ reverse proxy.
+
+If the gray screen persists, you can try disabling enhanced cookie protection and CSRF checks, and adjusting cookie settings:
+
+- `PGADMIN_CONFIG_ENHANCED_COOKIE_PROTECTION`: "False"
+- `PGADMIN_CONFIG_WTF_CSRF_CHECK_DEFAULT`: "False"
+- `PGADMIN_CONFIG_WTF_CSRF_ENABLED`: "False"
+- `PGADMIN_CONFIG_SESSION_COOKIE_SAMESITE`: "'None'"
+- `PGADMIN_CONFIG_SESSION_COOKIE_SECURE`: "True"
+
+This configuration relaxes session and CSRF settings and is known to resolve rendering issues when using pgAdmin in Docker inside Codespaces.
+
+- Option 1 is safer as it preserves CSRF protection.
+- Option 2 should be used only if the blank screen persists after Option 1.
+
+Always restart the pgAdmin container after changing environment variables.