It looks like maybe for some reason Matomo was not correctly installed. In the past these were known reasons for this:
WP-Matomo Integrationplugin is installed and configured to run in PHP mode. If that’s the case, we should detect this in the system report
WordFenceplugin is causing an issue. A user installed Matomo Beta, uninstalled it, and later installed it again from the WordPress directory and then this error appeared. It was fixed by deleting all the DB entries that contained
matomofrom these tables:
wp_wfFileModsas well as the
external_updates-matomoentry from the
wp_optiontable. This error likely only occurred while using the initial beta which was hosted on our servers and then updating the plugin from the WordPress directory. Please let us know if you still experience this issue.
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