> Here are the results from the calls to `window--dump-frame` (done on > Emacs 25.0.50.1): Thanks. Presumably with a maximized frame. > ========== one ============================== > right before `face-spec-recalc' > > frame pixel: 1920 x 971 cols/lines: 240 x 57 units: 8 x 17 > frame text pixel: 1888 x 971 cols/lines: 236 x 57 > tool: 0 scroll: 16/0 fringe: 16 border: 0 right: 0 bottom: 0 > > # parent: nil > pixel left: 0 top: 0 size: 1920 x 954 new: 0 > char left: 0 top: 0 size: 240 x 56 new: 0 240 is the "old" total width of your window. > normal: 1.0 x 1.0 new: 0 > body pixel: 1888 x 937 char: 236 x 55 > width left fringe: 8 left margin: 0 right margin: 0 > width right fringe: 8 scroll-bar: 16 divider: 0 > height header-line: 0 mode-line: 17 divider: 0 > > # parent: nil > pixel left: 0 top: 954 size: 1920 x 17 new: 0 > char left: 0 top: 56 size: 1920 x 1 new: 0 > normal: 1.0 x 1.0 new: 0 > body pixel: 1888 x 17 char: 236 x 1 > width left fringe: 8 left margin: 0 right margin: 0 > width right fringe: 8 scroll-bar: 16 divider: 0 > height header-line: 0 mode-line: 0 divider: 0 > > ============================================= > > ========== two ============================== > right after `face-spec-recalc` > > frame pixel: 1920 x 971 cols/lines: 192 x 46 units: 10 x 21 > frame text pixel: 1888 x 971 cols/lines: 188 x 46 Here we see the new default font set to 10 x 21, the various frame sizes remain unaltered as you observed. > tool: 0 scroll: 16/0 fringe: 16 border: 0 right: 0 bottom: 0 > > # parent: nil > pixel left: 0 top: 0 size: 1920 x 950 new: 950 > char left: 0 top: 0 size: 240 x 45 new: 56 The total width of your window remained unaltered at 240. Clearly the bug you observed. > normal: 1.0 x 1.0 new: ignore > body pixel: 1888 x 929 char: 188 x 44 > width left fringe: 8 left margin: 0 right margin: 0 > width right fringe: 8 scroll-bar: 16 divider: 0 > height header-line: 0 mode-line: 21 divider: 0 > > # parent: nil > pixel left: 0 top: 950 size: 1920 x 21 new: 0 > char left: 0 top: 45 size: 1920 x 1 new: 0 > normal: 1.0 x 1.0 new: 0 > body pixel: 1888 x 21 char: 188 x 1 > width left fringe: 8 left margin: 0 right margin: 0 > width right fringe: 8 scroll-bar: 16 divider: 0 > height header-line: 0 mode-line: 0 divider: 0 > > ============================================= > > ========== three ============================ > after doing `C-x 3` + `C-x 1` > > frame pixel: 1920 x 971 cols/lines: 192 x 46 units: 10 x 21 > frame text pixel: 1888 x 971 cols/lines: 188 x 46 > tool: 0 scroll: 16/0 fringe: 16 border: 0 right: 0 bottom: 0 > > # parent: nil > pixel left: 0 top: 0 size: 1920 x 950 new: 960 > char left: 0 top: 0 size: 192 x 45 new: 96 The total width got updated now to 192 as you observed. > normal: 1.0 x 1.0 new: 0.5 > body pixel: 1888 x 929 char: 188 x 44 > width left fringe: 8 left margin: 0 right margin: 0 > width right fringe: 8 scroll-bar: 16 divider: 0 > height header-line: 0 mode-line: 21 divider: 0 > > # parent: nil > pixel left: 0 top: 950 size: 1920 x 21 new: 0 > char left: 0 top: 45 size: 192 x 1 new: 192 > normal: 1.0 x 1.0 new: 0 > body pixel: 1888 x 21 char: 188 x 1 > width left fringe: 8 left margin: 0 right margin: 0 > width right fringe: 8 scroll-bar: 16 divider: 0 > height header-line: 0 mode-line: 0 divider: 0 > > ============================================= OK. The fix for Emacs 25 is attached. Please try it. I'm not yet sure whether to fix this for Emacs 24.5 as well. Basically, the fix "should" be harmless and resolve a problem not present in Emacs 24.3. However, wrong values for `window-total-width' or `window-left-column' should not really harm if they occur _only_ after setting the default font on a system whose window manager refuses to resize the Emacs frame as requested. Thanks, martin