Thread:Extension talk:FlaggedRevs/Error caused by FlaggedRevs when upgrading Wiki to 1.19/reply (2)

On the day when I reported the error I downloaded (as I suppose) the newest version of FlaggedRevs from ist page using Git Master (snapshot was temporarily not working). Today I downloaded again FlaggedRevs v. 1.19 but this time using a snapshot. And again an error appeares. This time when I try to launch a web updater (after uploading FlaggedRevs to an appriopriate directory and adding the demanded line to LocalSettings.php) I get the following error:

I presume I'm doing something wrong but I don't have the vauguest idea what I'm doing wrong...