Awesome!

Tab list view with previews of the webpage, excellent.

Many addons and browser have tried to tackle "Too many tabs" problem, but many of them fail -- either doing too much or too little. This add-on get the job done. I likes the feature that you can not only close the tab, but also move the tab into different windows.

Just a few suggestion for developer for UI
1. The default color of close button is red, and when you hover on it, it will become deep red.
I feel the color is too busy, creating a lot of distraction, especially when you have a lot of tabs (hence a lot of close button with bold red) . My suggestion is that close and pin down button should only be displayed (in gray) when hovering on the tab, and when user move cursor to close or pin-down buttons, they will become red.
An example like this is Tab Center Redux.

2. We should be able to customize the length and width of the tabber's pop-up window.

It's very useful, but it lacks a quick way to move tabs between windows (e.g. a "move to window" button).
Also, when first installed, it showed in the tab list a whole set of tabs that are not actually open (I have no clue about where it took them from).

EDIT: I found a new bug: it prevents tabs from auto-loading when selected. This is pretty annoying...

It works like a charm!

Colorful tabs list with ability to drag/drop tab order, pin/unpin, delete, and ESPECIALLY the abilityto peek at the tabs' content by hovering over it on the list. Would prefer a smaller font or resizeable window to avoid having to scroll when there are many tabs - also the ability to Undo deleted tab. Thanks for this wonderful extension!

It is easy to use and makes exploring the internet enjoyable. Great work!

This add-on serves as a long-awaited solution for tab management in Firefox Quantum. It includes the essential overview of tabs (including separation of multiple Firefox windows, if applicable). It also features two clever and highly useful components: a search bar and thumbnail previews of each tab, on hover). Clicked tabs focus into view while retaining the Tabby menu, which allows for easy navigation with the absolute minimum of clicks and distractions. This is a smart and simple tool. It has made me forget Tab Groups and is, by far, the best of the available tab manager add-ons. It does what is needed, contains components that are useful, and adds nothing else. It is difficult to think of anything that could be added to improve it. My only recommendation would be to keep it as-is. Its simplicity and lack of bloat sets Tabby apart from the rest. Outstanding!

Option to make font (and whole popup actually) smaller/resizable would be very helpful.

Excellent extension!!
Shortcuts to toggle between windows would make it perfect :)