Graphical pattern wraps to multiple rows

[richard-sim]

On a Win10 system with regular (non-HDPI) monitors the graphical pattern wraps to multiple rows in both Chrome 62 and FireFox. i.e. if there are 10 columns displayed, 7 will be in one row and 3 will be centred in another row. This happens with every number of columns, though it's not always 3 that are wrapped. Browsers are not zoomed in (set at 100%), and the windows are plenty large enough to encompass the grid size with a lot of horizontal room (~3x the grid) to spare. No errors are displayed in the developer console etiher.