The first light shedding on FF57above...
Thanks a lot keeping this excellent tool alive..
it also works perfect in Basilisk - the best FF fork for XUL and WebExt so far for a long time!

just a few suggestions:
i did not find any option to increase font size. !!
i would like to colorize background for example similar as dark style as in the old notepad.
some grey at nightime is more eye friendly.
import-export works pretty good between 2 browsers.
Loading speed first time is very slow.
it woud be nice to see tabs again, better than to open the hamburger menu panel to switch between notes.

finally its one of my prefered tools!