opensourcepos/app/Libraries/MY_Language.php

<?php
namespace app\Libraries;

use CodeIgniter\Language\Language;

class MY_Language extends Language {

	public function getLine(string $line, array $args = [])
	{
// if no file is given, just parse the line
		if ( ! str_contains($line, '.'))
		{
			return $this->formatMessage($line, $args);
		}

// Parse out the file name and the actual alias.
// Will load the language file and strings.
		[$file, $parsedLine] = $this->parseLine($line, $this->locale);

		$output = $this->getTranslationOutput($this->locale, $file, $parsedLine);

		if ($output === NULL && strpos($this->locale, '-'))
		{
			[$locale] = explode('-', $this->locale, 2);

			[$file, $parsedLine] = $this->parseLine($line, $locale);

			$output = $this->getTranslationOutput($locale, $file, $parsedLine);
		}

		// if still not found, try English
		if ($output === NULL || $output === "")
		{
			[$file, $parsedLine] = $this->parseLine($line, 'en');

			$output = $this->getTranslationOutput('en', $file, $parsedLine);
		}

		$output ??= $line;

		return $this->formatMessage($output, $args);
	}

}