Diễn đàn hỗ trợ Firefox

I'm trying to diagnose an unusual problem on a relative's computer elsewhere in the country via TeamViewer. When Firefox is initiated, the same picture (a man taking a shower) appears, and the VERY 'long URL starts with a Yahoo image file (yimg) and also contains buzzfeed.com well into that URL. I thought I could easily diagnose this, and have failed. Home page is set to blank page. I cleared all browsing data. When that failed I exported bookmarks, created a new profile, and the problem still continued, even before importing the bookmarks or adding any extensions. Something is retaining the unwanted startup behavior. Tonight, out of desperation, I will reconnect and look through the registry.

Can anyone surmise why an unwanted URL is being invoked upon Firefox startup?

Normally Firefox sponsor ads on home page occasionally inserts an new ad. I will support some occasional ads by clicking on the new ad to give Firefox 'click credit' then deleting new ad. Today when I delete the new ad another pops up 10-15 times an will not stop. That is too much. I do voluntarily support Firefox with monthly donation.

How do I stop the constantly returning ads?

I have used Mozilla Firefox as my default browser, for years. Recently, I used a program to clean (what it said was) junk files from my computer. Unfortunately, I did not make a rescue point. After removal of the files, several of my programs, including Firefox, has no longer worked as it once did. I was always able to go into settings to select my browser, my search engine, my home page, etc. That is no longer possible. I was wondering if I should uninstall Firefox and reinstall - or is their another easier way to repair my problem?

Any help I can get is much appreciated.

Starting with the most recent Firefox update a new small grey search bar containing the letters ENHAN appears in the upper right portion of my home page. It is intrusive and useless and I DO NOT WANT IT. How can I make it go away? I have Googled this extensively and have not found an answer. Please help. Thank you.