All-in-One Sidebar Alternatives
All-in-One Sidebar is described as '(AiOS) is a sidebar control, inspired by Opera . Click on the left edge of your browser window to open the sidebar and get easy access to all your panels' and is an app in the web browsers category. There are three alternatives to All-in-One Sidebar for Linux, Mac, Windows, Firefox and Pale Moon. The best alternative is The Good 'ol Sidebar, which is both free and Open Source. Other great apps like All-in-One Sidebar are OmniSidebar and Sidebar Switch.
The Good 'ol Sidebar (TGS) is a sidebar control, fork of All-in-One Sidebar .
The Good 'ol Sidebar vs All-in-One Sidebar opinions
CRITICAL TO ME, to open Bookmarks Library IN NEW WINDOW with single pane and telescoping folders.
0It improves upon the current features of All-in-One Sidebar and fixes a few bugs that were left broken in AiOS.
2
This add-on for Firefox provides a few options to make the sidebar more accessible and customize it.
Features
DiscontinuedThe add-on will not receive any more updates and will stop working by next November with Firefox 57, when XUL-based add-ons will be deprecated in favor of the WebExtensions API. See http://fasezero.com/ The extension still works on XUL-based Firefox forks like
Waterfox and 
Pale Moon
OmniSidebar vs All-in-One Sidebar opinions
JohnFastmanOmniSideBar is open-source (which All-in-One is not), reliable and highly functional. It's also more regularly updated than is All-in-One Sidebar, but offers the same functionality. I've used it for 2 years+ and never looked back.
-3Slim vertical button to toggle Firefox's (57+) sidebar on/off, on the left of browser. Firefox has native sidebar but no native switch to be touched on the edge of browser. This userChrome script provides experience like All-in-One Sidebar.
Features