https://support.mozilla.org/en-US/kb/how-to-set-the-home-page

Type about:config<enter> in the address bar. If a warning screen comes up, press the I Accept the Risk button. At the top of the screen is a search bar. Type browser.startup.homepage

What is the value? Right-click and select Reset to restore its default value; about:home

and few more things that i noticed are that > Firefox window is not signed in with my Firefox account (But I have signed it in) > No Firefox Add-Ons are available(I mean they are not started) > window which opens on startup is like its new window with no customization that I have made in Firefox.

Sometimes when the browser thinks there is a problem with the profile, it will create a new one.

Look on your desktop. Do you see a folder called; Old Firefox? Look inside. Look for the folder with the latest creation date.

https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

http://kb.mozillazine.org/Profile_folder_-_Firefox#Navigating_to_the_profile_folder

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Type about:profiles<enter> in the address bar. How many profiles are listed? How many should be there? Also, open the profile folder in your file explorer.

https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

Also, if this isn't a setting in Firefox, it might be part of your system startup or Scheduled Tasks. Microsoft has a tool that collects those for review:

https://docs.microsoft.com/en-us/sysinternals/downloads/autoruns

By the way, since you uninstalled Firefox, what happens at startup now? Does the URL open in your current default browser, or all is well?

By the way, since you uninstalled Firefox, what happens at startup now? Does the URL open in your current default browser, or all is well?

No, Now I don't see that website anymore.

Now, I have Reinstalled Firefox from (http://www.getfirefox.com/) And Still See That website on startup only on Firefox and not any other browser.

But I forgot to mention one more problem

Firefox was using all of available free CPU (Total CPU Usage reaching to 100%) and heating up my PC.

I checked it form Task Manager and ended that Task.

It does this same thing on every startup and I am forced to end task.

once I end task This doesn't trouble afterwards but does same thing on next startup.

this issue was also started approximately at same time as that website was autonomously opening up.

For some Help: At same time I had even started using web (https://www.naturalreaders.com/)

This same issue of High CPU usage also arose in Google Chrome when I used web and installed extension (https://www.naturalreaders.com/chrome_ext.html)

I think that after using this web's online reader (https://www.naturalreaders.com/online/) this new issue of High CPU Usage arose.

I would also like to bring to notice that CPU issue also starts up on every PC startup.

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible http://kb.mozillazine.org/Profile_folder_-_Firefox#Navigating_to_the_profile_folder https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles Type about:profiles<enter> in the address bar. How many profiles are listed? How many should be there? Also, open the profile folder in your file explorer. https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

I checked your suggestions [ about:profiles and about:config ] That all is okay.

There may be some malware on your computer that is set up to use Firefox. You could try running the cleaning tools suggested in this support article: Troubleshoot Firefox issues caused by malware.

There may be some malware on your computer that is set up to use Firefox. You could try running the cleaning tools suggested in this support article: Troubleshoot Firefox issues caused by malware.

I have Scanned my pc with all options

Malwarebytes

-Scan Summary- Scan Type: Threat Scan Scan Initiated By: Manual Result: Completed Objects Scanned: 372136 Threats Detected: 3 Threats Quarantined: 0 Time Elapsed: 3 min, 44 sec

-Scan Options- Memory: Enabled Startup: Enabled Filesystem: Enabled Archives: Enabled Rootkits: Disabled Heuristics: Enabled PUP: Detect PUM: Detect

-Scan Details- Process: 0 (No malicious items detected)

Module: 0 (No malicious items detected)

Registry Key: 0 (No malicious items detected)

Registry Value: 1 Trojan.Agent.VBS, HKU\S-1-5-21-505345203-3264771080-3318889684-1001\SOFTWARE\MICROSOFT\WINDOWS\CURRENTVERSION\RUN|Windows Updates Service, No Action By User, 1276, 755045, , , , , ,

Registry Data: 0 (No malicious items detected)

Data Stream: 0 (No malicious items detected)

Folder: 1 Trojan.Agent.VBS, C:\USERS\DELL\APPDATA\ROAMING\WINDOWS UPDATES FILES, No Action By User, 1276, 755045, 1.0.47856, , ame, , ,

File: 1 Trojan.Agent.VBS, C:\USERS\DELL\APPDATA\ROAMING\WINDOWS UPDATES FILES\Windows Updates Service.vbe, No Action By User, 1276, 755045, 1.0.47856, , ame, , 0EBE17656B27CC82D3746F9914B70025, A17030E2209D331A5532A67549A8992896421D6C03D5C7BCC05B1BACDD1B41ED

Physical Sector: 0 (No malicious items detected)

WMI: 0 (No malicious items detected)

(end)

___________________________________________________________

Since after scan And quarantined those files i have not seen any issue again

Looks like Issue solved

THANKYOU To ALL

Hello,

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution.

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