[Solved] message was cropped and render un-usable, sometimes, for chinese fonts.

You'll find a link to Gadgetbridge 'nightly' builds on this page: https://www.espruino.com/Gadgetbridge#how-to-set-up

Here's the bangle.js firmware updater on the app loader (there will be one file that's the 'cutting edge' one):
https://banglejs.com/apps/?q=fwupdate