Hi
Another regression I just observed: When sending 'vis 0, vis 1' to a canvas repeatedly, the window keeps moving to the top left of the screen. The offset is only a few pixels in each dimension. . I observe this with 0.49test3 (updated and compiled just now) on Ubuntu 18.04 (Gnome). This happens regardless of the menu wrapping of narrow windows. I checked again and it does not happen in 0.48 in different environments (Ubuntu 16.04 / Fluxbox, Ubuntu 18.04 / Gnome, Windows 10).
I wonder whether this is related to the recent 'Window Title Bar off screen' thread: What if the offset is exceptionally large there for some reason? I haven't thoroughly checked, but the help files don't use negative canvas positions.
Roman