Hello, // one right arrow key move of the cursor from the left most position // numbers differently in column-number-mode based on character encoding These steps reproduce the observed unexpected behavior: * emacs -Q /tmp/example.text * move cursor to line two at left most position, then right arrow key once * M-x column-number-mode * the modeline indicator shows (2,2) * move cursor to line nine at left most position, then right arrow key once * the modeline indicator shows (9,1) // for cjk the column number is two // for ascii the column number is one * expected modeline indicator to show (2,1) and (9,1) See attached: bug-report.text, example.text