PHP Fatal error on plugin activation : Uncaught Error: Call to undefined method Less_Parser::AbsPath()

WordPress Plugin
1

[07-Mar-2023 11:39:51 UTC] PHP Fatal error: Uncaught Error: Call to undefined method Less_Parser::AbsPath() in /srv/data/web/vhosts/site.com/htdocs/wp-content/plugins/matomo/app/vendor/wikimedia/less.php/lessc.inc.php:272
Stack trace:
#0 /srv/data/web/vhosts/site.com/htdocs/wp-content/plugins/matomo/app/vendor/wikimedia/less.php/lessc.inc.php(134): lessc->addParsedFile()
#1 /srv/data/web/vhosts/site.com/htdocs/wp-content/plugins/matomo/app/core/AssetManager/UIAssetMerger/StylesheetUIAssetMerger.php(48): lessc->compile()
#2 /srv/data/web/vhosts/site.com/htdocs/wp-content/plugins/matomo/app/core/AssetManager/UIAssetMerger.php(57): Piwik\AssetManager\UIAssetMerger\StylesheetUIAssetMerger->getMergedAssets()
#3 /srv/data/web/vhosts/site.com/htdocs/wp-content/plugins/matomo/app/core/AssetManager.php(206): Piwik\AssetManager\UIAssetMerger->generateFile()
#4 /srv/data/web/vhosts/site.com/htdocs/wp-content/plugins/matomo/app/core/View.php(356): Piwik\AssetManager->getMergedStylesheet()
#5 /srv/data/web/vhosts/site.com/h in /srv/data/web/vhosts/site.com/htdocs/wp-content/plugins/matomo/app/vendor/wikimedia/less.php/lessc.inc.php on line 272

WP : v6.1.1
WP RAM : 128 MB
PHP : v7.4.25
Matomo plugin : last version downloaded today, first installation

2

I am having the sam issue!

WP:6.2.2
PHP: 8.0.1

3

Hello @Thierry1 and @Jan-Ole_Potinius For us to investigate further could you please provide us the following:

  1. Copy of your system check report
  2. Php error logs.

There might be something in there that can help us identify where the issue is coming from.

4

Hello Emerson,

thanks for your reply. I cannot send a system check report as I cannot open that page. It causes a critical error.
A new installation of Matomo does not help. Matomo and WP run on the latest version.
PHP Error Log:
[16-Aug-2023 07:27:46 UTC] PHP Warning: Undefined array key 0 in …/wp-includes/class-wp-dependency.php on line 99
[16-Aug-2023 07:27:46 UTC] PHP Warning: Undefined array key 1 in …/wp-includes/class-wp-dependency.php on line 99
[16-Aug-2023 07:27:46 UTC] PHP Warning: Undefined array key 2 in …/class-wp-dependency.php on line 99
[16-Aug-2023 07:27:46 UTC] PHP Warning: Undefined array key 3 in …/class-wp-dependency.php on line 99
[16-Aug-2023 07:27:46 UTC] PHP Warning: Undefined array key 4 in …/class-wp-dependency.php on line 99

5

Thank you for sending your PHP log error @Jan-Ole_Potinius Could you please send us a list of the plugins installed? It might be an incompatibility issue.