[emacs CVS build 2009-05-13] Steps to repeat the bug: 0. Start `emacs -Q'. 1. Load attached file `emacs-bug.txt' with `C-x C-f'. 2. Load attached file `emacs-bug.el' with `load-file'. 3. Say `M-x make-first-line-invisible'. The first line properly disappears, however, the first character in the now visible part of the buffer (the letter `a') makes problems: It incorrectly refers to the character at buffer position 1 (the digit `1'). In particular, `C-u C-x =' for letter `a' shows --- character: 1 (49, #o61, #x31) preferred charset: ascii (ASCII (ISO646 IRV)) code point: 0x31 syntax: w which means: word category: .:Base, a:ASCII, l:Latin, r:Roman buffer code: #x31 file code: #x31 (encoded by coding system undecided-unix) display: by this font (glyph code) xft:-unknown-DejaVu Sans Mono-normal-normal-normal-*-21-*-*-*-m-0-iso10646-1 (#x14) Character code properties: customize what to show name: DIGIT ONE general-category: Nd (Number, Decimal Digit) There are text properties here: intangible t invisible t --- A side effect is that `C-a' no longer moves to the beginning of the line. Werner