Diagnosing TYPO3 Frontend Cache Issues When Backend Edits Don't Appear

Recognizable Condition

After editing page content, Fluid templates, or TypoScript in the TYPO3 backend, the changes are visible in the backend preview but not on the public website.

Cause & Diagnostic Table

Ordered Checks

1. Open the TYPO3 backend and go to System > Maintenance > Cache (or Install Tool > Cache Management). Note which cache groups are listed as active.
2. Make a trivial change (e.g., add a comment) to a Fluid template or page content and save.
3. Reload the affected page in a normal browser; observe whether the change appears.
4. If the change is missing, click Clear all caches in the same module.
5. Reload the page again in an incognito/private window (or with browser cache disabled) and check for the update.
6. If the update still does not appear, inspect HTTP response headers for signs of a reverse proxy (e.g., Via: Varnish or X-Cache: HIT).

Fixes Tied to Findings

• Stale frontend cache: Run typo3cms cache:flush --group pages or typo3cms cache:flush --group frontend from the project root. This requires CLI access with the same user that runs the web‑server process (often www-data or via sudo). After flushing, repeat the incognito check.
• Fluid view cache: Flush the fluid group: typo3cms cache:flush --group fluid.
• External proxy: Purge the URL in Varnish (varnishban req.url == "/path/to/page") or use the CDN’s purge API, then retest.
• Opcode cache: Restart PHP‑FPM or clear the opcode cache (service php8.2-fpm restart) if you edited PHP files.

Escalation Criteria

If after performing the above steps the frontend still shows outdated content:

• Verify that $GLOBALS['TYPO3_CONF_VARS']['SYS']['useCachingFramework'] is set to true in LocalConfiguration.php.
• Check the TYPO3 log (var/logs/*.log) for cache‑related warnings or errors.
• Confirm that no custom extension implements its own cache flush hooks that might be disabled; consult the extension’s documentation for additional flush commands.
• Consider enabling the debug mode temporarily ($GLOBALS['TYPO3_CONF_VARS']['SYS']['displayErrors'] = 1;) to see if any exceptions are thrown during cache generation.