Excess memory usage by Firefox extension

[eugenioperea]

Steps To Reproduce

1. Have the Firefox browser extension installed, on Ubuntu Linux.
2. Type about:processes in the address bar; notice that extensions are using an inordinate amount of memory
3. Type about:memory in the address bar, click the "Measure" button, click "extension"; identify the extension that is using the most memory. In my case, 230 MB
4. Type about:debugging#/runtime/this-firefox to identify the extension; it's Bitwarden
5. In comparison, the 2nd highest memory-using extension is at 27 MB

Expected Result

I expect the Bitwarden extension to use an amount of memory comparable to other extensions

Actual Result

The actual usage is nearly 900% higher than the second highest

Screenshots or Videos

Additional Context

No response

Operating System

Linux

Operating System Version

Ubuntu 24.10

Web Browser

Firefox

Browser Version

137.0 canonical-002 - 1.0

Environment Versions

Version: 2025.2.0 SDK: 'main (28c7e29)' Server version: 2025.3.3

Issue Tracking Info

• [x] I understand that work is tracked outside of Github. A PR will be linked to this issue should one be opened to address it, but Bitwarden doesn't use fields like "assigned", "milestone", or "project" to track progress.

[S-Kakar]

Thank you for reporting this issue! We've added this to our internal tracking system. ID: PM-19916

[p-himik]

Same here, only 3 times the size, at 716 MB. The second largest is 69 MB.

[jpiesing]

Same here. There are also a number of other posts in closed #10222 that were added after it was closed.

[4rft5]

My other twelve extensions put together only take up a range of between 20 and 100MB.

[eugenioperea]

Do we know if it's a memory leak? Does it only happen if we don't restart Firefox periodically?

[jpiesing]

Do we know if it's a memory leak? Does it only happen if we don't restart Firefox periodically?

For me, on Ubuntu, it's relatively sudden. I can do about:memory a couple of times a day and the number doesn't go up much. Then suddenly the fan goes on, the laptop starts swapping & firefox is very slow. Either something else gets killed or firefox gets killed or the system is just responsive enough that I can get a command line and kill Firefox.

[4rft5]

Do we know if it's a memory leak? Does it only happen if we don't restart Firefox periodically?

My screenshot was from just launching Firefox, so for me it's basically instantaneous.

[eugenioperea]

Hi, @S-Kakar. I know that you said that you had added this to your internal tracking system, but that was back in April, you've already closed another report, and we haven't heard anything from you guys. We would appreciate an acknowledgement that you're aware of our reports here.

[reyaz006]

1,148.67 MB here. Does it use Electron or something? Disabled website icons to see how it goes.

[nateRiver111]

Huge memory leak

this is 5 minutes after opening Firefox, eventually it hoards all the RAM and websites stops loading and you have to restart the browser

[Osrepnay]

some more information: for me, doing "Lock now" seems to release all the hogged memory, if about:processes is to be trusted

[ValueXu]

some more information: for me, doing "Lock now" seems to release all the hogged memory, if about:processes is to be trusted

Thanks, it works for me. Memeory usage of Bitwarden Chrome extension service worker changed from 900MB to 170MB