Separate Security Issue, please update your Flash 27.0 r0 by removing it with this tool : https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html Flash Player Version: 30.0.0.113 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only>

HI, please give your self a scan for any bitcoin mining malware or others that can cause the issue : https://www.adlice.com/download/roguekiller/

To be Checked and turned off unless needed for accessibility : Please : go to the Firefox 3 Bar Menu --> Options --> Privacy & Security panel and under Permissions check (put a tick in the box) the setting to Prevent Accessibility Services from accessing your browser.

Multi-Processor Support : Go to the 3 Bar Menu then Options --> General --> Performance and untick everything. change the recommended size lower then see how it runs. Note: 1 = No Multiprocessor = slow again. Try 2 Restart Firefox after making these changes please. Note : Hardware Acceleration is for Video Card, Monitor to see if remain off or to turn back on.

Only Disable as last resort.

Multi-processor Can completely disable it this way in about:config : dom.ipc.processCount set to 1 browser.tabs.remote.autostart = false browser.tabs.remote.autostart.2 = false

• http://kb.mozillazine.org/About:config

Only move to esr if low ram and old system.

Firefox Extended Release Version : Firefox ESR does not come with the latest features but it has the latest security and stability fixes.

• https://support.mozilla.org/en-US/kb/switch-to-firefox-extended-support-release-esr

If do please :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

How many tabs are open? Any other programs open? Is Firefox operating as single or multiprocess? Does this happen at the same time as a security software update? Do you have automatic updates on in Firefox? How much RAM does the device have?

EDIT: I see there's a big post coming in. I'm confused as to how it would specifically point to Flash or bitcoin miners though based on what the OP offered.

I have found Quantum takes all the RAM and crashes itself - not the computer.

I only had one tab open and no other programs running, and after 10 minutes browsing on ebay, for example, the pages took longer and longer to load until finally an error message came up to say my computer memory was running very low and it would have to close Firefox.

I immediately restarted Firefox and the browser worked really fast for about 10 minutes again, then ground to a halt.

I have been using Firefox for many years now and never had this type of problem. I shouldn't have to start editing or altering my computer setup just to get this browser to work - after all there are plenty of other options in the market that do work properly - however I prefer to stick with Firefox.

Is there a fix or update for this problem yet?

I am using version 61.0.1 64 bit on Windows 7 with a P7450 @ 2.13GHz and 4GB RAM. The computer easily copes with CS5 Photoshop, Illustrator, Indesign etc. even with multiple images open in each program.

So why is Quantum using up resources and ending up so slow?

Hi Jems1, it sounds as though your crashes are different from those affecting the original poster.

Could you start a new question?

https://support.mozilla.org/questions/new/desktop/fix-problems

In your report, please include, if possible:

(A) Crash report IDs

If you are getting the Mozilla Crash Reporter form, your Firefox may have logged some data that would help track down the cause of the problem. You can submit that data to Mozilla and share it with forum volunteers to see whether it points to the solution. Please check the support article "Firefox crashes - asking for support" for steps to get those crash report IDs from the about:crashes page (or, if necessary, from disk).

(B) Any difference when testing in Firefox's Safe Mode

In its Safe Mode, Firefox temporarily deactivates extensions, hardware acceleration, JavaScript compilers, and some other advanced features of Firefox that might make it more prone to crashing on some systems.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" Help > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Does Firefox crash sooner, later, not at all?