Worked well initially but I think the author periodically wipes out stored notes on his server. Not good if so. I've moved over to OurStickys which allows sync with Google accounts.

I really wish I could have rated this higher, as it is exactly what I needed except that it wasn't reliable. You cold not rely on a stickie sticking to a web page. You could return to that very page five seconds after having placed a stickie on it and it would not be there. Even if you hit hide/show stickies repeatedly. I relied on these stickies for short notes such as shipping costs or price per item reminders on products I was considering. It was disappointing that these stickies would not be there on the page when I returned.

the irony is that this addon doesn't work in https://addons.mozilla.org/. I wanted to use it to remember if something didn't work.
didn't tried it in a big number of websites, but it seem to work ok outside of this place.
ctrl+shift+c opens developer console for me.
I'm using manjaro linux 18 / firefox 68.0.1
forget what i said, this doesn't work, it is bugged and doesn't let me remove it from my system

Works on 1 Mac but not on another. The Sidebar is empty. (Reinstall doesn´t ake any difference)

AddOn not reliable

How is one to use this with android without a mouse?
I have tried many note add-ons and this is the only one that installs on android firefox, BUT I can't get the damn notes to show up on a page?
I dont see any "sidebar" like you mentioned.
Please inform me how to use this. Do I need to create custom gestures or something?