Reviews of Sleep Mode

By: matico Add-on

List of user reviews and ratings for Sleep Mode

Total ratings

3.53 (Rating count: 30)

Receive review notifications

Get notified when new reviews are posted so you can respond quickly.

See reviews on Firefox Add-ons Store

View and respond to reviews directly on the store page.

Visit

Review summary

Sleep Mode is praised for real memory and CPU savings by sleeping inactive tabs, often dramatically cutting RAM use and improving battery life. However, the timer is frequently unreliable, enabling/disabling can reload tabs and disrupt sessions, and Linux users report crashes. It can also break tab-opening behaviors. Users want more granular controls (per-tab sleep/whitelisting) and easier timer updates. Overall, it’s effective when working but plagued by stability and usability issues that hinder everyday use.

Pros

Significant RAM savings by sleeping inactive tabs
Lower CPU usage and longer battery life when tabs are slept
Overall positive and effective when the feature works

Cons

Timer feature is unreliable or non-functional (doesn't reset or apply correctly)
Enabling/disabling can reload all tabs or discard-loaded tabs, breaking the session
Causes instability on Linux and Firefox crashes in some setups
Disrupts normal tab opening (middle-click/ctrl-click) and URL handling
Limited settings and lack of per-tab controls/whitelisting; timer updates require disabling and restarting

Upgrade to see all 33 reviews

User Reviews

Recent rating average: 3.80

All time rating average: 3.53

Upgrade to see all 33 reviews

12% (4)

Date	Author	Comment
2026-01-08	DO*****

2025-05-05	ka*****	This extension is brilliant, really. But it would be even better if one could set it to start automatically on browser startup
This extension is brilliant, really. But it would be even better if one could set it to start automatically on browser startup
2025-05-04	ly*****

2025-03-31	远离*****

2025-03-03	Za*****	By putting all my tabs to sleep it only saved 6% of my ram usage. On top of that, the time based function doesn't work. I will still put all tabs in sleep mode. I'd like the unused once to be but to sleep after X time, that way they tabs to have to always re-load each time I switch back and forth.
By putting all my tabs to sleep it only saved 6% of my ram usage. On top of that, the time based function doesn't work. I will still put all tabs in sleep mode. I'd like the unused once to be but to sleep after X time, that way they tabs to have to always re-load each time I switch back and forth.
2025-02-28	敬念*****

2024-12-07	Fi*****	An excellent application, unfortunately it doesn't work properly. I'd like my tab to sleep after X minutes without me coming back to it. To allow me to go back and forth without constantly reloading, example: if I come back to this tab after leaving it in less than a minute, don't put it in sleep mode.
An excellent application, unfortunately it doesn't work properly. I'd like my tab to sleep after X minutes without me coming back to it. To allow me to go back and forth without constantly reloading, example: if I come back to this tab after leaving it in less than a minute, don't put it in sleep mode.
2024-02-13	Tá*****

2023-12-20	Fi*****	unfortunately too few setting options or the setting options offered do little to change the behavior
unfortunately too few setting options or the setting options offered do little to change the behavior
2023-10-10	Kr*****	Sleep Mode is a good idea, don't get me wrong. I've use this extension for a very long time while on Windows and without any problems until now. A few weeks after switching to Kubuntu 23.04 and then to Fedora 38 later, Firefox began crashing almost immediately. Disabling all extensions and re-enabling them one by one in Safe Mode traced the cause of all Firefox-related crashes back to this Sleep Mode extension. Because of this, I cannot in good conscience recommend the Sleep Mode extension to anyone until this fatal bug has been fixed on Linux!
Sleep Mode is a good idea, don't get me wrong. I've use this extension for a very long time while on Windows and without any problems until now. A few weeks after switching to Kubuntu 23.04 and then to Fedora 38 later, Firefox began crashing almost immediately. Disabling all extensions and re-enabling them one by one in Safe Mode traced the cause of all Firefox-related crashes back to this Sleep Mode extension. Because of this, I cannot in good conscience recommend the Sleep Mode extension to anyone until this fatal bug has been fixed on Linux!