Revert "Clarification of the neccessary autoloading of plugins in the error message"

This reverts commit e4cf4880fd7cc40989fcbed117af5538f109b45e.
Revert "Incorporated the last change about plugin autoloading to all relevant error messages"

This reverts commit 42b10863edfd4e88b8a56329f5d299c92b6e44cc.
Refactor error message
Put in an element, outside the wrong conditional scope