fontHeight not working in E.showMenu()

on menu item selection, screen is cleared, menu time function is executed, and menu is drawn again

Yes, I think that's intentional as we were getting some glitches in apps I think.

font height

Argh - sorry. Yes, it looks like the Bangle.js implementation blindly overwrites the fontHeight setting. I'll try and get a fix in for this but it may not be for a week or two - just filed an issue here: https://github.com/espruino/Espruino/issues/2043

In the mean time, this is the menu implementation for Bangle.js: https://github.com/espruino/Espruino/blob/master/libs/js/banglejs/E_showMenu.js

So if you do E.showMenu = function(items) { ... } and change the code in there you can have a menu exactly as you want. If you saved it as a file newmenu.boot.js you could even make it take the place of all existing menus in Bangle.js