Thread:Project:Support desk/Fatal error: Interface 'Psr\Log\LoggerInterface' not found

Hello,

Update to the latest version of mediawiki failed when running update script and when displaying pages: Fatal error: Interface 'Psr\Log\LoggerInterface' not found in /var/www/parts-unknown/org/mediawiki/core/includes/debug/logger/Logger.php on line 46

This would be version 1.23.6, although I can't verify it with the Special:Version page, because I get the error above.

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