First impressions were actually pretty good, except my usecase requires something that can run in the sidebar alongside whatever page(s) I am viewing (and that's a deal-breaker). I'll keep searching.

Excellent add-on, thanks. Only thing I would like to see is the ability to increase the size of the text.

Excellent, just what I was looking for. If I was allowed one tweak, then I'd have the red note icon showing in the tab when it's pinned. A part from that PERFECT! Many thanks

Exactly what i was looking for.I wish i knew this add on earlier.I just wanted a simple text editor with dark them that also has folder/tabs.This did it for me.Thanks to the author

It's fantastic of course, but I just recently lost all my notes because I had to reset windows (no lost files) but this still wiped the notes from the system. Some kind of sync, even to Gdrive or Onedrive would be incredible, it's my fault for not considering they could vanish on me like this... --There isn't an easy way to export notes either-- (Untrue, there is a export to text option I had missed). It's a nice, simple addon, but you have to mind it more than I think most would considering its simplicity. Thank you tho...

This is a great extension. I like the way you can open up folders and how you can separate notes. Easy to backup and import.

I started using when Mozilla announced that their Notes extension will no longer Sync as of Nov 1st.

The only way this extension can become better is by adding syncing.

Отличная записная книжка. Не хватает только "внятной" печати, оформления текста, копирования в записку.
There is a lack of good print from the extension and styling of the text (bold, italic, etc.), and copy from page to notes. Great notes.

[13:55 EEST, 5.5.2019] From TextNotes developer:
Now it works properly for me on my windows 10 again.

[5.5.2019] From TextNotes developer:
There is an error in Firefox why you can not use your TextNotes and you can not download it again.

https://www.theverge.com/2019/5/4/18529456/mozilla-firefox-extensions-bug-certifications-error-fix
https://www.ghacks.net/2019/05/04/your-firefox-extensions-are-all-disabled-thats-a-bug/

Please wait for the fix from Mozilla! It will be ready soon.

Simple and convenient addition.
Not enough in the context menu item - Add to TextNotes.
In context menu does not display items TextNotes (win10).

Отличное дополнение! Очень удобное и функциональное! Не хватает только возможности использовать различные стили текста (жирность, курсив, подчеркивание и т.д.).

Super text notes :-)

Context menu option is not available. Despite having it added to FF, you can still see "add to FF". Couldn't figure out how to use it.

Reply to developer :- I use FF 62.

This is a great note taker. However as most of us have seen updates to Firefox can disable addons with incompatibility issues. The export feature in this addon does not produce a readable file so you are on your own if something dies. You will have no backup available unless you can reload the addon. Which is not all bad but a concern none the less. Based on this I could not give it 5 stars and it has not been updated in quite a while, possibility the author has abandoned it. You can't blame the authors for that because they rarely get any remuneration for their efforts. Its worth using but I keep a text file backup and will keep my eyes open for something else.

I like this add-on for its simplicity. An improvement for me would be for it to be protected by a password and stored in the Firefox browser stored logins.

UPDATE: I have been using this addon for some time now and what I miss most is a search function, especially as I now have more than a dozen notes.
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A very nice and useful add-on! I have used Quicknote in the past but it has become obsolete so I tested several other similar add-ons and I found this one to be the most convenient for me.
My only complain is that those .tn files exported as backup are not readable. I see it has been mentioned again so I hope this functionality becomes available soon!

it seems like Opera

Awesome app —great replacement for all the sticky notes apps on Opera, from which I migrated from —this is powerful & versatile. I really am delighted to use this, it helps me immensely, & I've been much much more productive thanks to this behemoth of an add-on !!! The scrollbar helps, also would be nice to have formatting features like Bold, Italic, Underline. Plus please add a .JSON or similar format (I don't know wutev's readable & can be saved to the computer to be read by text editor.) Sync'ing would be nice too ! Keep the updates coming. Search would be handy too. :Þ Thanks !! P.S: An Import\Export option _in_ the add-on workspace (built-into the Editor UI itself) & not Tools > Addons > Import\Export would be muuuch appreciated, like how V7 Notes on Opera works, currently the feature-set in the in-app workspace is bland & limited, please consider these in the next version soon ! Also, a Read-Only option for some entries would be nice !

Very good and simple.
I wish that textnotes can be synced between instances. Perhaps via firefox extensions or 3rd. cloud service (onedrive, google drive)

Nice ...
However, for (my) real convenience, I would modify it like this :
a) limit the writing zone to the sidebar ... so to have the web page on the right without switching tabs ... and without using notepad++ and switching from a webpage to notepad++ with CTRL+tab
b) add a shortcut such as F4 to open/close it quickly in the sidebar ...

There is no use to replace NOTEPAD++ within Firefox ... the only real use of such an addon is giving user a chance to write or copy and paste in the sidebar links, snippets of text, etc ...

;-)