Hi, I also have the same problem.
This only occurs when there is a character select menu. The value that keep changing is the Canvas Pos Y value. The Pos Y value fluctuate between 7.9877** and 7.988**
The Canavs Pos X,Y,Z values in character select menu are different from other menus.
In character select menu, pos X = 0 , pos Y = between 7.9877** and 7.988**, pos Z = -31.90075
When resize the game window in character select menu, the pos X,Y,Z value do not change.
When resize the game window in other menu, the pos X and Y change value while pos Z always remain 0.
I also notice the width or height value when there is decimal are also different in character select vs other menu. The difference in value is around 0. something.
Thanks for the help.