blank page after switching language

[keneso]

Working on v2.1.0 on local (php 8.2) I installed bootstrap template, and cloned it, they would work fine with the default language set to English, when I changed default to Italian the page went blank, it stayed blank even when changing back to English.
It works fine with the responsive classic, but not bootstrap or its clone; no changes to either of them.

Peculiar fact is that I did the same on a live server, and it does not go blank, and works fine with both bootstrap, and its clone.

The log file reports:
PHP Fatal error: Uncaught Error: Undefined constant "TEXT_HEADER_ARIA_LABEL_NAVBAR" in C:\path-to\zencart\includes\templates\bootstrap\common\tpl_header.php:25

Not a big problem, as I can work on the live server, just curious to understand why in local behaves like this.

[lat9]

On your local site, check to see if any files named header.php (not lang.header.php) exist in any of these directories, where bootstrap-clone is the name of your cloned bootstrap template:

/includes/languages/english
/includes/languages/italian
/includes/languages/english/bootstrap-clone
/includes/languages/italian/bootstrap-clone

[keneso]

Thanks.
No header.php or lang.header.php in the directories you suggested, however it put me on the right track, perhaps I was tired when adding the Italian package, and missed to copy it into the extra_definitions directory, did so, and all is fine.