UPDATE!
In other thread @Niko_S mentioned, that for him the problem was caused by the plugin “Smash Balloon Custom Facebook Feed Pro”. I’ve realized, that this is my case as well. If I deactivate the plugin, everything is ok.
I’m not sure wheather the problem is caused just by the other plugin, or it is just a hint, what’s the problem in Bricks. It should be mentioned, that other parts of the dashboard are ok, the translation problem is there only in Bricks.
And since I’ve installed the Smash Ballon plugin the same day as I updated Bricks to 1.9.1.1, I cannot tell wheather the problem was there before or not.