does NOT work in FF 38+ Rated 1 out of 5 stars

Tested in Firefox 38 on Ubuntu.

Labels show up, but cannot be activated, rendering the addon useless. Moreover, the labels are generated alphabetically, without taking the keyboard layout into account; for example, QWERTY D, F, J and K keys are under the strongest fingers on the home row, thus should be preferred for website parts that are most likely accessed by the user (e.g., a large textarea, a link to the next page).

I recommend using VimFx instead.

Rated 3 out of 5 stars

Looks awesome ^_^

But it's not working on Firefox 32 & Ubuntu 14.04 :-( ( Hotkeys show up but do not work )

Rated 5 out of 5 stars

Very cool !! It will be good if there is a option to choose the activation key and option to choose links to be opened in foreground or background tabs.

Edit: I think the default behavior should be to open the links in new foreground tabs and when press and hold ctrl to open the links in the same tab.Shift or Space key will be convenient to use. Also short key to enable/disable the addon.

This review is for a previous version of the add-on (0.1.1-signed.1-signed). 

Thanks for your advice.
Could you tell what keys you prefer, such as shift key , alt key , or some combination keys?
About the foreground or background tabs, I will realize it as the activation key.