Mozilla will shut down Pocket’s services on July 8, 2025. At that time users will no longer be able to access the Pocket website, apps and API. You can export your saved items and API data until October 8, 2025 before they are permanently removed. For more information, see this article.

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

When Firefox is on, Desktop Window Manager consumes a lot of RAM

  • 4 replies
  • 2 have this problem
  • 148 views
  • Last reply by unavailable

I have multiple monitors and most often have Firefox windows open on each. Lately, I've been noticing that the Desktop Window Manager process is consuming a huge amount of RAM. At the same time, consumption completely disappears with the closing of Firefox windows. Video: https://i.imgur.com/pHCa7Hh.mp4 (I left it for a while then closed Firefox windows) After a while, I noticed that already 13 GB of memory is being used by DWM. I don't know if sites affect behavior, but most often I have https://music.yandex.ru/home open

OS: Windows 11 (Microsoft Windows [Version 10.0.22621.1928]). Firefox: 115.0.1 (64-bit) Screen setup: 1 - 3840 x 2560 with 200% scale, 2 - 1920 x 1080 with 100% scale.

I have multiple monitors and most often have Firefox windows open on each. Lately, I've been noticing that the Desktop Window Manager process is consuming a huge amount of RAM. At the same time, consumption completely disappears with the closing of Firefox windows. Video: https://i.imgur.com/pHCa7Hh.mp4 (I left it for a while then closed Firefox windows) After a while, I noticed that already 13 GB of memory is being used by DWM. I don't know if sites affect behavior, but most often I have https://music.yandex.ru/home open OS: Windows 11 (Microsoft Windows [Version 10.0.22621.1928]). Firefox: 115.0.1 (64-bit) Screen setup: 1 - 3840 x 2560 with 200% scale, 2 - 1920 x 1080 with 100% scale.
Attached screenshots

Chosen solution

It does not! And I disabled "Use hardware acceleration when available", now there is no memory consumption.

Seems like hardware acceleration is a culprit

Read this answer in context 👍 0

All Replies (4)

I don't think it's OK

Bump, still not fixed.

Appears only when I move the Firefox window to the built-in display (1920x1080 with 100% scale)

Does it also happen in Troubleshoot Mode?

Chosen Solution

It does not! And I disabled "Use hardware acceleration when available", now there is no memory consumption.

Seems like hardware acceleration is a culprit