this is a very complicated one. Problem was when updating from 2.4.0 to 2.5.0-b1 the updater wanted to update all dimensions (meaning alter all columns in log_visit, link_action and conversion) to the same column type. This was happening because the system did not know those dimensions were already installed from a previous Piwik version. There was an update script that was supposed to tell Piwik those components are actually already installed since we only moved them from core to plugins but it cannot work as it is an update as well and therefore not executed before the actual update check. I tried many solutions to overcome this issue including reverting all the columns to the initial MySql Schema but even then there are problems as some plugins like DevicesDetection are not defined in MySql Schema but in the plugin. It is especially complicated since users might update from 2.4 to a future version where the column type of one of those dimension changes and we need to make sure to actually execute an alter update if one of those dimension changes. In such a case we cannot directly mark the component as successfully recorded. The conclusion was for me it is only possible to solve this problem by listing all dimensions that were moved from core to plugins including their version at that time hard coded...