Hi, please explain and expand on why you think Firefox has a memory leak please.

Firefox gradually slows when left open, and Task Manager shows its memory use gradually balloons over time (currently sitting at ~2.23 GB after being open about two hours). Closing tabs does nothing.

Running 64-bit Firefox on Windows 10, with 16 GB RAM and an i7 Skylake processor.

(Wanted to answer "I've got bits of molten RAM card dripping out onto the floor. Here's your sign." :P)

Hold on, on a hunch I closed the Firefox sidebar, and it's possible the memory leak might be in my Google Hangouts extension rather than Firefox proper (the memory usage fell by quite a bit). I'll leave the tabs open a while and see what happens over time.

EDIT: Nope, still growing. Was down to 2 GB but now it's up to 2.39.

LOL, ya that would be a sure sign of a memory leak, a little messy also.

Since Firefox is now multi-thread and multi-processor it is expected that Firefox should use more ram. As well add-ons take approx 20megs each give or take. It should not be excessive. If it is the extension you mention you should report that to the Developer of the extension and check their support page/s for any information. Also make sure you are running the current version offered from their page. You can force a check in Firefox from the add-ons page by clicking the gear icon and check for updates.

Please make sure in Options --> Privacy & Security there is a Check Mark in the box to Prevent accessibility services from accessing your browser. Then go to 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. https://www.howtogeek.com/334594/stop-complaining-that-your-browser-uses-lots-of-ram-its-a-good-thing/

Please let us know if this solved your issue or if need further assistance.