No longer needed, as "unload tab" is now built into Firefox, but 5 stars for the years of usefulness and inspiring Firefox to build in this functionality.

Well, it didn't work when I tested it just now, but I think it must have probably worked before? When I first started using it.
Today, a new-features list appeared in my browser after opening. Including:
"Right-click on one or multiple tabs and choose Unload Tab to help Firefox stay fast."
I am glad this is becoming a stock feature. o7 Thanks for the help in the meantime :) Godspeed

Thank you so much Frederik.

Simple and reliable. Fully under your control - unlike Auto Tab Discard, which messes Firefox up if you have too many tabs.

Users: Suggest using an optional feature to indicate which tab has been discarded:

1. Firefox toolbar "hamburger menu" (a button with three horizontal lines near the top right) > Add-ons and themes, or Firefox top horizontal menu > Tools > Add-ons and themes.

2. Locate "Discard Tab"

3. tab Preferences > check: Prepend snowflake to discarded tabs.

非常好用，但只能休眠当前标签，要是能支持休眠当前标签组就好了。

I just installed it 1 min ago and I've just tried to freeze and unfreeze one tab, so I don't know how/if it works in the long term. But it seems to be good for now.

My one problem with it is that I wish it had a visual effect on the tabs that you freeze so that you know which tabs are or aren't. Like a blue border around the tab would be nice.

Also I don't really understand why it's referred to as "Discarding" tabs, I think freezing or suspending is more accurate, discarding would imply completely getting rid of the tab...

What's missing is the ability to discard an open tab. For example discard the current tab and open the last used one

>>> PLEASE ADD TOOLBAR BUTTON AS WELL AS RIGHT-CLICK! :P <<<

Sometimes when discarding Youtube tabs the other already open tabs from any website become blank and they stay blank even if i reload the page(F5 or CTRL + F5), only fix seems to be restarting Firefox.

Exactly what I'm looking for!

Awesome, works as intended. If there are "Discard other tabs", "Discard tabs to the right" and "to the left" then it would be perfect.

The addon requires you to have a certain version because mozilla instead of waiting to have their web extension things figured out completly before implementing they decided to release it without finishing so as new versions release they add new stuff that addons can do and unloading tabs is only able to be done on that version fordward.