Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

• Do NOT click the Reset button on the Safe Mode start window or otherwise make changes.

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

--- You can remove all data stored in Firefox from a specific domain via "Forget About This Site" in the right-click context menu of an history entry ("History > Show All History" or "View > Sidebar > History") or via the about:permissions page.

Using "Forget About This Site" will remove all data stored in Firefox from that domain like bookmarks, cookies, passwords, cache, history, and exceptions, so be cautious and if you have a password or other data from that domain that you do not want to lose then make a note of those passwords and bookmarks.

You can't recover from this 'forget' unless you have a backup of the affected files.

It doesn't have any lasting effect, so if you revisit such a 'forgotten' website then data from that website will be saved once again.

Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

Do a malware check with some malware scanning programs on the Windows computer.
Please scan with all programs because each program detects different malware.

Make sure that you update each program to get the latest version of their databases before doing a scan.

• Malwarebytes' Anti-Malware:
  http://www.malwarebytes.org/mbam.php
• SuperAntispyware:
  http://www.superantispyware.com/
• Microsoft Safety Scanner:
  http://www.microsoft.com/security/scanner/en-us/default.aspx
• Windows Defender: Home Page:
  http://www.microsoft.com/windows/products/winfamily/defender/default.mspx
• Spybot Search & Destroy:
  http://www.safer-networking.org/en/index.html
• AdwCleaner:
  http://www.bleepingcomputer.com/download/adwcleaner/
  http://www.softpedia.com/get/Antivirus/Removal-Tools/AdwCleaner.shtml
• Kasperky Free Security Scan:
  http://www.kaspersky.com/security-scan

You can also do a check for a rootkit infection with TDSSKiller.

• Anti-rootkit utility TDSSKiller:
  http://support.kaspersky.com/5350?el=88446

See also:

• "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked

thank you so much the  : Reset Firefox to its default state, seems that helped now is OK like it was before

the problem is comming from a file name log.txt is keeping big and big every time now the size is 30gb and is keeping growing how can I fix that the file is located on

C:\Users\computer\AppData\Roaming\Mozilla\Firefox\Profiles\55zj9vsl.default\extensions\{E4091D66-127C-11DB-903A-DE80D2EFDFE8}\logs

now is 149 gb please help

Remove the "ImageHost Grabber" addon.

In order to uninstall a possibly unwanted extension, please do the following:

1. From the Firefox window click the Firefox button at the top left and select Add-ons, or, if the Firefox button is not shown, click the Tools menu and click Add-ons.
2. Once the Add-on Manager has opened in a new tab, click the Extensions button on the left side of the window.
3. You should now see a list of your installed extensions on the right side together with buttons on the right side of each extension.
4. To remove an extension from Firefox, simply click the Remove button. You should see a message that informs you about the successful removal of the add-on.
5. Note that some add-ons require a Firefox restart to be removed completely. To perform a Firefox restart after the add-on removal, click the Restart now link in the message.

You can find further information about uninstalling extensions in the following articles:

Disable or remove Add-ons

Remove a toolbar that has taken over your Firefox search or home page

so is that "ImageHost Grabber" who did that ?

It is a addon you or another program on your computer installed and it has the ID {E4091D66-127C-11DB-903A-DE80D2EFDFE8} so that must be causing your problem.

I'm the one who installed to be able to download images so is there any other addon like "ImageHost Grabber" can i used to download images from webs like deviantart

well you should remove it and see if it resolves the issue first before you try to find alternatives.

you should also try to delete the file after uninstalling the addon (for now)

I did remove it and remove the file now the HD have 200GB free space

Hello. The log feature is disabled by default. There's a warning message in the window that allows you to enable it:

"Enabling/Disabling the following options will require a restart of Firefox in order to take effect. They should only be enabled temporarily to log a specific event, and then disabled right away. Leaving them enabled will cause Firefox to run slow, chew up memory, and eat up hard drive space."

Normal users shouldn't enable it, it's just for developers.

You can re-install IHG. Go to IHG's settings window and select "Debugging". Then make sure to uncheck "Enable Console Logging" and "Enable Debugging Logging". Click on "Clear Log" to clear the log file and then restart Firefox. After that you can use IHG again and the log file will be an empty file (0 bytes).

I recommend you to install the latest beta version: http://imagehost-grabber.com/index.php?page=download