Firefox Community Forum

When i start fire fox it immediately opens 10 additional versions in the background which I can see in task manager and they take up a lot off memory. If i end task them they immediately come back. This only started recently. I noticed it because now when i open say a youtube video it shows it as number 4. This never happened before unless I had the same video open more than once.

If I can not stop this I will have to uninstall.

Been using Firefox for over a decade. But lately is has become so slow now. Often freezes up if more than two tabs are open or a website is in any way very complex. What settings and issues should I check? What has changed? I can run the same sites on Brave and Edge browsers with no issues or not nearly as slow and bogged down.

I am on a new PC with Windows 11, using 4 monitors. I keep trying to figure out what is making my mouse and sometimes the keyboard behave sluggish (freezes for a moment). I have takes all suggestions that AI has suggested but it is still happening. Do you have any thing for me to try? It appears to be only when Firefox is running.

Gentlemen, isn't your browser using a lot of RAM? I've been freaking out about it in recent years. That's only with 25 tabs open!! Despite the fact that the system was installed just a day ago, without any tweaks!!!

Two questions; First is why does the Taskbar show "Firefox (2)" (see first image) Second: When trying to troubleshoot, I open Task Manager, and with just one tab open, I see Firefox (13); confirmed when the line is expanded. What is going on here and is it impacting Firefox performance; see 2d and 3d images? (Phone camera photos as PrintScreen is disabled for Task Manager which doesn't seem smart)

Hello, I'm on Firefox Nightly 152.0a1 running on a freshly installed new Windows 11 version. I've used Firefox exclusively for my whole life and everything has always been smooth until a few days ago. Firefox started (and continues) to freeze for a second or two pretty regularly, each time I use the search bar for example, open a new tab, while a page is loading (which is very slow at the moment) but also scrolling on a page for example. During the freezes, the temperature of my CPU also increase by approximately 20°C. CPU usage in task manager shows that it is quite high, 10x higher than Edge that I opened for comparison only : https://i.imgur.com/enuMMZl.png.

I have sought the internet for advice but nothing changed this behaviour. I updated my computer through Windows Update, my drivers through Driver Booster, I disabled hardware acceleration on Firefox, I removes all AI components with zoicware/RemoveWindowsAI on GitHub, I changed dom.ipc.processPriorityManager.backgroundUsesEcoQoS on about:config to false but nothing cured the problems.

I'm out of solutions and I don't know if I should be waiting for another Nightly build (usually there's about 1-2 a day but 152.0a1 is sticking since a few days and there isn't any update available since, seemingly), if there's others energy economy parameters I could play with on Windows 11 that I don't know about or if something else is in the way. Any help very appreciated, thanks!

after working in firefox for a while and using a number of windows and the I close firefox with multiple windows open in my session. if i open it again and keep doing this for a while and then have closed firefox, eventually I can no longer open a firefox window and get a message the I have too many windows opn and can't open more till i close the open windows. i hover over the firefox app and all the previously closed windows are stacked up. why didn;t they close when i exited my firefox sessions. why are they still there and clogging up the system?

I love Firefox and have used it forever. But its memory usage is killing me lately and I'm seriously reconsidering.... PC, Win11, Intel7, 16GB memory. (I'm typing this from Chrome)

I've updated, restarted, but it keeps maxing out and slowing my computer to a crawl. Somebody please tell me there's a fix pending?

Not sure if this is a Firefox or YouTube bug.. it's really annoying and happens quite a few times each day I use my PC.. Is there any solution to this or perhaps reverting the update til this is resolved? I usually wait fo rit to stop lagging or if I'm not patient enough.. I'll just close Firefox entirely and re-open. Thanks.

For the last couple of days, the Firefox instance goes black and the title bar turns to an old windows look (see picture). Or turns fully blue, the color of browser theme, and the title bar is covered as well. There is no certain page that makes this bug appear, it appears randomly regardless of the page I'm visiting. Often it happens on the Firefox instance that is on the monitor I'm not working on at that moment. For example, I am browsing on my main monitor, and the 2nd monitor has a page open, the page in the 2nd monitor becomes bugged. It happens the other way too. Current Firefox version is 149.0 64 bit version, but i think it happened before the update too. I have already tried to turn hardware acceleration on and off again.

I started noticing my browser was running rough, and I tracked it down to Youtube, but only when I have a video in fullscreen. It doesn't appear to be affected by the codec, av0/avc/vp09 all suffer from it.

Incognito mode (no extensions) is still affected by it, but a separate profile + troubleshoot mode are not. My RTX 5080 is showing about 2% usage when playing a video, 0% at idle.

How do I nail down what's causing this?

Select the text in the text input box to type (overlay typing), the Chinese input method will flash, then nothing will be typed and the selected text will disappear. 在文本输入框中选中文字进行打字（覆盖打字），中文输入法会闪一下，然后什么也打不出来并且选中的文字也不见了。 As in the following figure, it almost always happens when you select and overwrite text. 就像下面图中情景一样，对文字进行选择覆盖的时候几乎一定会发生。

在 Firefox 内部：

通过 JS 触发的新页面 通过 a.click 触发的新页面 甚至 rel=noopener 都会被标记为：

“related browsing context”

进而共享同一个进程，新页签因为内存占用过高，导致旧页签卡死。

通过设置

1. 添加 COOP 响应头 add_header Cross-Origin-Opener-Policy "same-origin" always;也无法解决

设置空白页再重定向也无法解决