Systeminfo page works only in English - OJS 3.3.0-16 with php-intl installed

Hello!

Describe the issue or problem
After we upgraded from 3.3.0-6 to 3.3.0-16, the systeminfo page didn’t show correctly in our main locale. But surprisingly, in English it would.

Steps I took leading up to the issue

  1. Install multiple languages in your OJS
  2. Assure to have php-intl installed properly
  3. Set the locale to English
  4. Go to the systeminfo page. It works
  5. Change your active locale
  6. Go to the systeminfo page. It’s blank

What application are you using?
OJS 3.3.0-16 with 8.2 php

Additional information
When the active locale is English, the following code return value “C” and the systeminfo page works.

    if (empty($locale)) {
      error_log("Locale: <empty>\n", 3, "/tmp/my.log");
      // get current locale
      $locale = setlocale(LC_TIME, '0');
    }

If the active locale is for example Italian, the page is blank.

We read some posts (this and this) about php-intl, and we tried to set the Intl locale value to “it-IT”. Now the systeminfo page is well displayed in Italian (because it’s set directly in Intl) and in English (because the default “C” value works). But it’s still blank in any other locale.