Tab Snooze - allows you to close a tab and have it reappear at a chosen time later
Domain Volume Control / Better Volume Booster - allow you to set default volume per-domain (note that unfortunately, in the 1st one the set volume gets changed when you change the volume through a site’s player, and the 2nd one currently causes an issue on Nightly with unpaused videos)
Playback speed - allows you to change the speed of videos/audio on any site, even only by x0.01 at a time (you can also change the buttons that appear when you click on the addon in the toolbar/addons menu to have specific speeds readily available) (note that it doesn’t change the pitch of the audio)
Specifically for YouTube you can also use an addon like Improve YouTube. To configure the feature click on the addon in the toolbar/addons menu > Shortcuts > Playback speed. To change the shortcut so that you hold Ctrl and use the mousewheel (while hovering over the video) click Ctrl and release it before using the mousewheel up or down accordingly (otherwise it acts as a zoom to the settings window)
Media URL Timestamper - automatically inserts the current timestamp of the YouTube/Twitch video you’re watching and updates it in the history in case you accidentally close/navigate away from the page or go to a different time in the video
Feedbro - an RSS reader with filtering capabilities
It’s not for saving memory but to postpone a tab to check it later (for example to see new comments on a post, or if you don’t currently have time to read an article and want to read it tomorrow)
Tab Snooze - allows you to close a tab and have it reappear at a chosen time later
Domain Volume Control / Better Volume Booster - allow you to set default volume per-domain (note that unfortunately, in the 1st one the set volume gets changed when you change the volume through a site’s player, and the 2nd one currently causes an issue on Nightly with unpaused videos)
Playback speed - allows you to change the speed of videos/audio on any site, even only by x0.01 at a time (you can also change the buttons that appear when you click on the addon in the toolbar/addons menu to have specific speeds readily available) (note that it doesn’t change the pitch of the audio)
Media URL Timestamper - automatically inserts the current timestamp of the YouTube/Twitch video you’re watching and updates it in the history in case you accidentally close/navigate away from the page or go to a different time in the video
Feedbro - an RSS reader with filtering capabilities
Can’t Firefox already do this though?
Right-click > Unload Tab on a tab.
It’s not for saving memory but to postpone a tab to check it later (for example to see new comments on a post, or if you don’t currently have time to read an article and want to read it tomorrow)