Hello

Try Start in Safe Mode:

• Firefox in safe mode

I think this can be a virus , so:

• Problems caused by malwares

Or try Reset Firefox:

• Reset Firefox

Sometimes unwanted browser add-ons are included with various free software downloads. You could try this:

Disable ALL nonessential or unrecognized extensions on the Add-ons page. Either:

• Ctrl+Shift+a
• orange Firefox button (or Tools menu) > Add-ons

In the left column, click Extensions. Then, if in doubt, disable.

Usually a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step.

Any improvement?

See also:

• http://malwarefixes.com/mixidj-claro-search-com-removal-steps/