Can you see if those instances with descent of 5 are because the
character is displayed using a different font, by any chance?
Another, perhaps more probable cause could be that in some cases
CURRENT_MODE_LINE_HEIGHT uses the value of w->mode_line_height, and
sometimes it needs to estimate the height by calling
estimate_mode_line_height. Maybe something is inconsistent between
the estimation and the actual value.
Also, the offending character is displayed on the mode line, right?
Could you please show a screenshot of a window with the mode line
formatted as it should when Emacs freezes?
It freezes randomly in different modes (Python, Clojure, shell, diff, magit, …). Check screenshot how it looks like in almost all of them.
If the screenshot will not go through, here’s link:
R.
