Great add-in!!
It could be better if it was option to save links (right click menu)..

Add the ability to remove from the context menu

Very useful to put some link in the sidebar, instead of opening multiple tabs, when I work on several sites at the same time. But a sync function is missing.

EDIT: And also folders are missing. I would prefer to have a sync with this addon.

I also miss "Save-to-Read". This looks like it will do the same thing. I prefer saving things to a folder in bookmarks than the 'magical' 'secret' places the other similar add-ons use. I also like the simple list you get by looking at the list with your bookmarks tools later and sorting them anyway you want.

I wish there was a way to just 'pin' a folder in the list for the 'star' option in the search/url bar, but this works almost as well.

I found a bug. when i add one page, the icon show red "NaN". FireFox version 59.0.2

It's a very useful add-on for me, and also many thanks if you can add a time sequence option( ex. New at top).