The biggest bug is that you can’t scroll down to see the words you were just studying on the Session Completed page without making the page so small you cannot see the words anyway. And there is the same issue with being unable to scroll down to see the leader board on the second Session Completed page. The leader board can be nice to see sometimes for motivation and a sense of community in this endeavor, but being able to see the words you just studied can be really important at times when you are struggling to learn some of the words. That is the major bug that I see, or maybe it is just a horrible web design that needs to be fixed. Here is an image of what the page looks like if you take the time to make contents of the Session complete page small enough to be able to see all 10 of the words that you studied:
Notice the distortion in the heads of the columns.
One other thing that I find does not work at all is the keyboard shortcuts that are theoretically available in the session itself. They just plain do not work.
There is also some sort of bug that puts a sort of black “o” over the end of the wrong answer that you entered in the “You wrote” section of the window where you are to enter the correct answer. You can see this in the image below
The other thing that may seem aesthetically pleasing, but is not nearly as functional as the old format is the expandable window that gets wider as you enter the tiles for the tile exercises. It works great if you enter the tiles perfectly the first time, but if for whatever reason you did not enter them all perfectly the first time it is much more awkward to selectively remove tiles because of the way they move around in the window as it is shrinking. A window of a fixed width, which may be able to expand downward for longer phrases would be much more functional for the tile exercises.