numx, textx and selx were compile-time constants stored per layout;
the number column starts at PopupPad and text at PopupPad+PopupNumw,
which dat.h now says once. The height fallback tried dropping the
marker, then the preedit, then the padding as three separate refits;
below one padded row it now shows as many bare rows as fit, at least
one, which is what those steps added up to.
font.c exported three wrappers for one function, and the fit == -1 mode
existed only for the tests; textdraw() takes fit and colour. win.c
tested the empty picture in the thread and again in winshow, interned
two atoms by hand next to getatom(), kept a consumer-side drain that the
producer's already guarantees never finds anything, zeroed ten globals
before returning from the only thread that read them, and re-checked
sizes that resizebacking had just established. The page marker is laid
out once and drawn from the layout instead of being recomputed.
