Two things, do them separately or at the same time. Don't know what's best.
Bring out the web console ( Ctrl+shift+c). And see what output you get there when trying to upload.
Have another tab open with the Web IDE that is connected to your Bangle. Then again, try upload from the App Loader. See what output you get to the Web IDE console.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Two things, do them separately or at the same time. Don't know what's best.
Ctrl
+shift
+c
). And see what output you get there when trying to upload.