Firefos and or Thunderbird cause my PC to run slow

After I’ve been using Firefox and or Thunderbird my PC starts to run slowly system wide and not just in Firefox, even Google Chrome runs slowly it seem that pages with graphics and ads with video in them make Firefox and Google Chrome run slow or maybe it’s Firefox that cause my whole system to run slowly I’ve had the problem of Firefox Running slowly in Ubuntu Cylon Linux 12.04 but it did not effect my entire system, just Firefox and I would just use Chrome to view that particular page that ran slow in Firefox. Sometime closing Firefox fixes the problem other times I have to log off and log back on to Linux. Chrome will get a error Shockwave is not responding at the top of the browser window and selecting stop the plug in does not fix the slow system problem and then I get a Chrome is not responding and I click Kill to close Chrome. I think maybe it might be Firefox that is causing this problem to start or maybe Thunderbird because closing one of both of them seems to fix the problem to somewhat but my system still seems to run slow after that and tasks like opening a folder or drive in file manager becomes sluggish.

Please open a terminal and enter…

Code:
inxi -b

and post the output.

System: Host: Taslims-Ubuntu-Mate Kernel: 4.4.0-24-generic x86_64 (64 bit)
Desktop: MATE 1.12.1 Distro: Ubuntu 16.04 xenial
Machine: Mobo: ASUSTeK model: P8B75-M v: Rev X.0x
Bios: American Megatrends v: 1002 date: 10/16/2012
CPU: Dual core Intel Core i3-3220 (-HT-MCP-) speed/max: 1604/3300 MHz
Graphics: Card: Intel Xeon E3-1200 v2/3rd Gen Core processor Graphics Controller
Display Server: X.Org 1.18.3 drivers: intel (unloaded: fbdev,vesa)
Resolution: [email protected]
GLX Renderer: Mesa DRI Intel Ivybridge Desktop
GLX Version: 3.0 Mesa 11.2.0
Network: Card: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller
driver: r8169
Drives: HDD Total Size: 3160.6GB (58.8% used)
Info: Processes: 215 Uptime: 3:55 Memory: 1048.9/3632.1MB
Client: Shell (bash) inxi: 2.2.35

Some ideas:

As for the ads displayed in your browser, I would really suggest an adblocker, either Adblock Plus or what I recommend, UBlock. It is especially useful on older hardware where ads can take the system to a halt when they pop up in your browser.

The other thing would be to block Flash content by default, only allow it when needed.

Then, Chrome can take a lot of RAM if many tabs are open. Firefox is lighter in this regard but then the Flash version on Firefox is almost obsolete, it really makes it slower.

I think it has something to do with Firefox and the Flash plugin because Firefox has always been a problem in Linux but not Windows or even Android I never have these problems with Firefox in Windows 7 or on my Android Tablet. I think Firefox causes such problems that it effects the entire system until I close it and wait a while for it to completely close and the system recovers because after awhile from closing Firefox everything goes back to normal and my PC runs quickly again. I’ve installed a bunch of other Browsers including Opera and they work better and are more stable then Firefox. I will install the Ad Blockers you mentioned because Ads are annoying anyway and totally Useless.