on facew book my "Share Button" does not work
on face book my "Share Button" does not work unless I open the post then I can share it. when it does work a box opens off screen its on the next post or if I go to a new Facebook page & like it then try to set the Notifications it opens the box below the page so as soon as you move the mouse the box disappears so I cannot change any settings Windows 10 FireFox 42.0 Thanks Jim
Hey there, first thing I would do, is to check your java plug-ins under the menu "add-ons" -> plug-ins, and see if you need to update any of them.
Second, if you have any add-ons installed is to restart FF in safe mode and see if it has the same problem here is the link to restart FF in safe mode -> https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode#w_how-to-start-firefox-in-safe-mode.
Once you've done that check the FB page and see if the problem persist. If it doesn't do it, try to enable your add-ons one at the time and restart every time. If the problem comes up again after a specific add-on has been re-enabled, you've got it! You can then eliminate that add-on and try to find an alternative for it.
after that you can try a system update for windows making sure you have latest version with latest java and so on, I'm a Mac user so I'm not sure what's the go for windows.
Sounds like a problem with the CSS code that positions the button in the wrong place possibly by using an absolute position instead of attaching the button to the current mouse position.
Can you reach this button with the tab key in case there are elements with have a tabIndex?