Firefox 93 on Windows to unload tabs when it detects the system is running on low memory. Mozilla believes the feature reduces Firefox memory usage and out-of-memory crashes. Users need to click on the unloaded tab to reload.
Tab unloading in Firefox
New Microsoft Edge has Sleeping Tabs to improve memory, CPU, battery life, and performance. Chrome has tab discarding.
While Edge freezes tabs and releases resources from tabs that are put to sleep, Chrome discards tabs. Microsoft Edge offers more control and options for Sleeping Tabs than Chrome.
Mozilla, inspired by Chrome, two years back, implemented tab unloading in Firefox 67.
The feature comes into effect in Firefox and applies to tabs when the system runs out of memory only.
Firefox team unable to figure out low memory condition on users machines, disabled the feature until they have more data and confidence to turn on in public versions of Firefox.
Firefox 93 gets automatic tab unloading
Mozilla is bringing the feature back to Firefox with Firefox 93 on Windows and with the following release aimed at Linux and Mac.
The company is planning to create an equivalent page for Firefox tab unloading also, similar to chrome://discards.
Modern Web browsers with multi-process architecture consume more memory.
Even if you have a high-end system with higher RAM installed, your system may consume more resources when running multiple apps.
In this situation, Firefox unloads tabs and releases resources, thus reduces memory and makes the system responsive and stable.
The user needs to click on the unloaded tab to reload. You’ll benefit from the feature.
Anytime, the feature can be controlled by pref
browser.
This was set to True for me in Firefox 93 Nightly. Toggling its value to false in about:config disables it.
Extensions such as Dormancy and Unload Tab can do this, Mozilla is baking this into Firefox natively.
Let us hope Mozilla will get tab unloading right this time.
What do you say about this? Let us know in the comments below.
More on Firefox:
Mozilla is disabling High Contrast Mode in Firefox on Mac w/ v91.0.2
Firefox 91.0.1 fixes a bug that exposes Tabs from Private browsing in Normal Windows
