... if the upgrade happens when viewing (or coming from) the sitemapxml tool's page, since the language constants associated with the installation are included in the plugin's main language file:
[20-May-2023 12:16:49 UTC] Request URI: /mysite/myadmin/index.php?cmd=login&camefrom=sitemapxml.php, IP address: 127.0.0.1, Language id 1
#0 [internal function]: zen_debug_error_handler()
#1 C:\xampp\htdocs\mysite\myadmin\includes\languages\english\sitemapxml.php(33): define()
#2 C:\xampp\htdocs\mysite\myadmin\includes\modules\sitemapxml_install.php(13): require_once('C:\\xampp\\htdocs...')
#3 C:\xampp\htdocs\mysite\myadmin\includes\init_includes\init_sitemapxml.php(96): require_once('C:\\xampp\\htdocs...')
#4 C:\xampp\htdocs\mysite\includes\autoload_func.php(40): require_once('C:\\xampp\\htdocs...')
#5 C:\xampp\htdocs\mysite\myadmin\includes\application_top.php(42): require('C:\\xampp\\htdocs...')
#6 C:\xampp\htdocs\mysite\myadmin\login.php(8): require('C:\\xampp\\htdocs...')
#7 C:\xampp\htdocs\mysite\myadmin\index.php(11): require('C:\\xampp\\htdocs...')
--> PHP Warning: Constant HEADING_TITLE already defined in C:\xampp\htdocs\mysite\myadmin\includes\languages\english\sitemapxml.php on line 33.
... if the upgrade happens when viewing (or coming from) the
sitemapxml
tool's page, since the language constants associated with the installation are included in the plugin's main language file: