Error: Call to undefined function Doku_Handler_Parse_Media()

[Juergen-aus-Zuendorf]

Hi,

under the old Dokuwiki release "Librarian" the Button plugin generates an error. Just open a page with buttons, go to edit and save the page. Then you get the following error message:
"Error: Call to undefined function Doku_Handler_Parse_Media()"

The Dokuwiki logs give this informations:

2026-09-02 08:27:55
Error: Call to undefined function Doku_Handler_Parse_Media()
/var/www/html/wiki/lib/plugins/button/syntax.php(286)
#0 /var/www/html/wiki/inc/parser/renderer.php(126): syntax_plugin_button->render()
#1 /var/www/html/wiki/inc/parser/renderer.php(141): Doku_Renderer->plugin()
#2 /var/www/html/wiki/lib/plugins/include/syntax/include.php(157): Doku_Renderer->nest()
#3 /var/www/html/wiki/inc/parser/renderer.php(126): syntax_plugin_include_include->render()
#4 /var/www/html/wiki/inc/parser/renderer.php(141): Doku_Renderer->plugin()
#5 /var/www/html/wiki/lib/plugins/include/syntax/include.php(157): Doku_Renderer->nest()
#6 /var/www/html/wiki/inc/parser/renderer.php(126): syntax_plugin_include_include->render()
#7 /var/www/html/wiki/inc/parserutils.php(691): Doku_Renderer->plugin()
#8 /var/www/html/wiki/inc/parserutils.php(158): p_render()
#9 /var/www/html/wiki/inc/parserutils.php(97): p_cached_output()
#10 /var/www/html/wiki/inc/Ui/PageView.php(67): p_wiki_xhtml()
#11 /var/www/html/wiki/inc/Action/Show.php(40): dokuwiki\Ui\PageView->show()
#12 /var/www/html/wiki/inc/template.php(120): dokuwiki\Action\Show->tplContent()
#13 [internal function]: tpl_content_core()
#14 /var/www/html/wiki/inc/Extension/Event.php(134): call_user_func_array()
#15 /var/www/html/wiki/inc/Extension/Event.php(200): dokuwiki\Extension\Event->trigger()
#16 /var/www/html/wiki/inc/template.php(102): dokuwiki\Extension\Event::createAndTrigger()
#17 /var/www/html/wiki/lib/tpl/bootstrap3/main.php(117): tpl_content()
#18 /var/www/html/wiki/inc/actions.php(30): include('...')
#19 /var/www/html/wiki/doku.php(131): act_dispatch()
#20 {main}

Best regards
Juergen

[rpeyron]

Hello, that is a little strange, I am not able to reproduce with Librarian release (I have tried with docker image linuxserver/dokuwiki:2025-05-14-ls266 which is the oldest Librarian image available from linuxserver).

I guess it is related to the latest fix for Mort: 2c97a74 ; you can try to revert to previous version, or add this line at the start of the button/syntax.php file:

if (!function_exists('Doku_Handler_Parse_Media')) require_once(DOKU_INC . 'inc/parser/handler.php');