Hello Malcolm18,

The preference "browser.newtab.url" has been removed some time ago ....

"Trovi" : what was that BT operator thinking  ? ! Please see : https://malwaretips.com/blogs/trovi-search-removal/

Would you try this please :

Reload the page : Hold down the Shift key and left-click the Reload button or press 'Ctrl + F5' or press 'Ctrl + Shift + R'

If that doesn't make a difference, then please try this :

Clear the Firefox cache :

https://support.mozilla.org/en-US/kb/how-clear-firefox-cache

"Remove the cookies" from websites that cause problems :

https://support.mozilla.org/en-US/kb/delete-cookies-remove-info-websites-stored (scroll down to : "Delete cookies for a single site")

'Hope that helps .....

Thank you for your help, much appreciated. I have done all the actions you suggested but I am afraid to no avail. By the way I confirm I don't have & never had Trovi. Dredging my mind back I think BT Yahoo Mail and Yahoo Mail did some alterations and split something but I was told at the time to ignore it as it would be d/w by them automatically. Possibly red herring !

I don't think that you will find an answer here, but maybe you
could post a question :

https://help.yahoo.com/kb/SLN15838.html

https://io.help.yahoo.com/contact/index?page=home&locale=en_US&y=PROD_ACCT

Can you attach a screenshot?

• https://support.mozilla.org/en-US/kb/how-do-i-create-screenshot-my-problem
• use a compressed image type like PNG or JPG to save the screenshot

You can try these steps in case of issues with web pages:

You can reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files.

• hold down the Shift key and left-click the Reload button
• press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
• press "Command + Shift + R" (Mac)

Clear the Cache and remove the Cookies from websites that cause problems via the "3-bar" Firefox menu button (Options/Preferences).

"Remove the Cookies" from websites that cause problems:

• Options/Preferences -> Privacy & Security
  Cookies and Site Data -> Manage Data

"Clear the Cache":

• Options/Preferences -> Privacy & Security
  Cookies and Site Data -> Clear Data -> Cached Web Content: Clear

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is is causing the problem.

• switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
• do NOT click the "Refresh Firefox" button on the Safe Mode start window

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

Hi there, Thank you so much for trying to help. A colleague of Mozilla called McCoy sent the info re clearing caches etc and this did not solve the problem. I attach the requested screenshot. Not sure what you can see from this but the contacts icon is the first, (next to messages) on the right handside (on the same level as the Compose button ) these icons should be above the Compose button, not sure if this is the underlying cause. Thanks again

I seriously doubt if this has anything to do with your problem, but your system details show that you have this extension installed :

"IObit Surfing Protection & Ads Removal "

As this add-on is not listed on the official addons.mozilla.org page : did you install it yourself  ?

Would you (just to make absolutely sure) disable it and see if that will make a difference  ?

As you don't have this problem using Edge - if everything else fails you could consider to Refresh Firefox :

https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

Thank you for your prompt response, sorry delayed reply but been busy, a friend of mine has just passed away. I have been in contact with Yahoo and they say everything is fine and working correctly. There only advice is to switch to Chrome or some other browser. I have uninstalled the IObit prog also others & I have also uninstalled Firefox and reinstalled it. I regret it is all to no avail. It looks as tho' it's one of those ! all I can do is use F'fox as normal and use Edge, Chrome etc when I need to edit Contacts.

My sincere condolences on the passing of your friend.