ediff: Customizing the Mode Line
7.11 Customizing the Mode Line
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When Ediff is running, the mode line of ‘Ediff Control Panel’ buffer
shows the current difference number and the total number of difference
regions in the two files.
The mode line of the buffers being compared displays the type of the
buffer (‘A:’, ‘B:’, or ‘C:’) and (usually) the file name. Ediff tries
to be intelligent in choosing the mode line buffer identification. In
particular, it works well with the ‘uniquify.el’ and ‘mode-line.el’
packages (which improve on the default way in which Emacs displays
buffer identification). If you don’t like the way Ediff changes the
mode line, you can use ‘ediff-prepare-buffer-hook’ to modify the mode
line.