Error: Class "DOMDocument" not found

[HMJR]

After updates to:
Release 2026-07-14b "Mort" and sprintdoc dw

PHP 8.2.31 litespeed
Linux 4.18.0-553.141.2.lve.el8.x86_64

PDF
Error: Class "DOMDocument" not found
An unforeseen error has occured. This is most likely a bug somewhere. It might be a problem in the dw2pdf plugin.
More info has been written to the DokuWiki error log.

Error log:

2026-08-18 12:06:55
Error: Class "DOMDocument" not found
/home/fp/domains/name/public_html/nl/lib/plugins/dw2pdf/src/Writer.php(172)
#0 /home/fp/domains/name/public_html/nl/lib/plugins/dw2pdf/src/Writer.php(145): dokuwiki\plugin\dw2pdf\src\Writer->fixInternalLinks()
#1 /home/fp/domains/name/public_html/nl/lib/plugins/dw2pdf/src/PdfExportService.php(180): dokuwiki\plugin\dw2pdf\src\Writer->renderWikiPage()
#2 /home/fp/domains/name/public_html/nl/lib/plugins/dw2pdf/src/PdfExportService.php(116): dokuwiki\plugin\dw2pdf\src\PdfExportService->renderDocument()
#3 /home/fp/domains/name/public_html/nl/lib/plugins/dw2pdf/src/PdfExportService.php(59): dokuwiki\plugin\dw2pdf\src\PdfExportService->buildDocument()
#4 /home/fp/domains/name/public_html/nl/lib/plugins/dw2pdf/action.php(74): dokuwiki\plugin\dw2pdf\src\PdfExportService->getPdf()
#5 /home/fp/domains/name/public_html/nl/inc/Extension/EventHandler.php(80): action_plugin_dw2pdf->convert()
#6 /home/fp/domains/name/public_html/nl/inc/Extension/Event.php(75): dokuwiki\Extension\EventHandler->process_event()
#7 /home/fp/domains/name/public_html/nl/inc/ActionRouter.php(85): dokuwiki\Extension\Event->advise_before()
#8 /home/fp/domains/name/public_html/nl/inc/ActionRouter.php(51): dokuwiki\ActionRouter->setupAction()
#9 /home/fp/domains/name/public_html/nl/inc/ActionRouter.php(64): dokuwiki\ActionRouter->__construct()
#10 /home/fp/domains/name/public_html/nl/inc/actions.php(19): dokuwiki\ActionRouter::getInstance()
#11 /home/fp/domains/name/public_html/nl/doku.php(131): act_dispatch()
#12 {main}

[Klap-in]

I think this error happens because the php-xml extension is missing. Could you add it to your server (and restart Apache)? We do not mention it yet in the requirements, but it is recently introduced to do some link rewrites to enable better caching.

[HMJR]

Hi Klap-in,

Just to be sure: which of these three extensions xmlreader, xmlrpc, or xmlwriter do you mean?

[Klap-in]

On Ubuntu/debian and CentOS / RHEL / Fedora: it seems to be in the php-xml package (install via your package manager). For alpine Linux in php-dom package. So please check for the OS you use. I do not know about the distinction you are mentioning, probably if you do a Google/etc search you can find what to use for your system.