protected function getTagTemplateName($identifier, $isInline)
    {
        if (isset($this->customTagsConfiguration[$identifier])) {
            return $this->customTagsConfiguration[$identifier]['template'];
        }

        // BC layer:
        $configurationReference = $this->tagConfigurationNamespace . '.' . $identifier;

        if ($this->configResolver->hasParameter($configurationReference)) {
            $configuration = $this->configResolver->getParameter($configurationReference);

            return $configuration['template'];
        }
        // End of BC layer --/

        $this->logger->warning(
            "Template tag '{$identifier}' configuration was not found"
        );

        if ($isInline) {
            $configurationReference = $this->tagConfigurationNamespace . '.default_inline';
        } else {
            $configurationReference = $this->tagConfigurationNamespace . '.default';
        }

        if ($this->configResolver->hasParameter($configurationReference)) {
            $configuration = $this->configResolver->getParameter($configurationReference);

            return $configuration['template'];
        }

        $this->logger->warning(
            "Template tag '{$identifier}' default configuration was not found"
        );

        return null;
    }