I've migrated from my old dw server to a new one and this errors started to appera on some pages:
Warning: Undefined array key "hid" in html.php on line 114
How to fix this problem?
Impossible to say. You didn't tell us anything about the version of your DokuWiki, what kind of server, what php version or, indeed, anything.
It is strange. The error is gone, but new errors appeared:
Warning: Undefined array key "REMOTE_USER" in /var/www/html/dokuwiki/lib/plugins/data/helper.php on line 506
Warning: Trying to access array offset on value of type null in /var/www/html/dokuwiki/lib/plugins/data/helper.php on line 507
Here is the page:
Here is the info:
Lighttpd, php8.1, Dokuwiki Igor. Debian 11
It would be good to know which template you are using, and which plugins are installed... and also whcih version of PHP this is running on...
I had similar errors under PHP 8.1, but everything seems to work under 8.0 ... just as a hint.
Copied the whole dokuwiki directory on another server with PHP 7.4. All errors are gone