* doc/lispref/display.texi (Customizing Bitmaps): Add a note
regarding the order of bits being the opposite of that in
XBM images. (Bug#40784)
either a string or a vector of integers, where each element (an
integer) corresponds to one row of the bitmap. Each bit of an integer
corresponds to one pixel of the bitmap, where the low bit corresponds
-to the rightmost pixel of the bitmap.
+to the rightmost pixel of the bitmap. (Note that this order of bits
+is opposite of the order in XBM images; @pxref{XBM Images}.)
The height is normally the length of @var{bits}. However, you
can specify a different height with non-@code{nil} @var{height}. The width