ERROR_REPORTING_DISPLAY_VERBOSE

BigPipe::sendNoJsPlaceholders in core/modules/big_pipe/src/Render/BigPipe.php

Sends no-JS BigPipe placeholders' replacements as embedded HTML responses.

BigPipe::sendPlaceholders in core/modules/big_pipe/src/Render/BigPipe.php

Sends BigPipe placeholders' replacements as embedded AJAX responses.

error_displayable in core/includes/errors.inc

Determines whether an error should be displayed.

FinalExceptionSubscriber::isErrorLevelVerbose in core/lib/Drupal/Core/EventSubscriber/FinalExceptionSubscriber.php

Checks whether the error level is verbose or not.

HttpExceptionNormalizer::buildErrorObjects in core/modules/jsonapi/src/Normalizer/HttpExceptionNormalizer.php

Builds the normalized JSON:API error objects for the response.

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