Notice (8): Trying to access array offset on value of type null [APP/Controller/ProjectsController.php, line 44]
Warning (512): Unable to emit headers. Headers sent in file=/var/www/desarrollo/workrocca/vendor/cakephp/cakephp/src/Error/Debugger.php line=970 [CORE/src/Http/ResponseEmitter.php, line 71]
Warning (2): Cannot modify header information - headers already sent by (output started at /var/www/desarrollo/workrocca/vendor/cakephp/cakephp/src/Error/Debugger.php:970) [CORE/src/Http/ResponseEmitter.php, line 168]
Warning (2): Cannot modify header information - headers already sent by (output started at /var/www/desarrollo/workrocca/vendor/cakephp/cakephp/src/Error/Debugger.php:970) [CORE/src/Http/ResponseEmitter.php, line 197]
Error: Expression `user_id` is missing operator (IS, IS NOT) with `null` value.

Expression user_id is missing operator (IS, IS NOT) with null value. 📋

InvalidArgumentException
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CORE/src/Database/Expression/QueryExpression.php Toggle Arguments
            $operator = '!=';
        }
        if ($value === null && $this->_conjunction !== ',') {
            throw new InvalidArgumentException(
                sprintf('Expression `%s` is missing operator (IS, IS NOT) with `null` value.', $expression)
            );
        }

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