You can add the absolute path to the sprite image file or you can try putting a forward slash / in front of images or ../ in front of images.
Examples:
li#twitter {left:50px;width:22px;background:url('/images/spritesheet.png') -50px 0;}
or
li#twitter {left:50px;width:22px;background:url('../images/spritesheet.png') -50px 0;}
or
li#twitter {left:50px;width:22px;background:url('https://www.example.com/wp-content/themes/example-theme/images/spritesheet.png') -50px 0;}
Unfortunately, you cannot add a link to a specific BuddyPress/bbPress reply:
@ John – We have tried adding the bbPress Reply ID before and it is stripped out of the Twitter share posting window/box. Example code: <li id="twitter"><a href="http://twitter.com/share?url=<?php echo the_permalink(). '#post-' .bbp_get_reply_id(); ?>" target="_blank" rel="nofollow" title="Twitter"></a></li>.
The URL in the Browser Address bar shows the complete URL including the Anchor Tag #. Example: #post-0000. There is no workaround solution for Twitter because Anchor Tags and Hash Tags that Twitter uses conflict with each other. An Anchor Tag on Twitter is converted to a Twitter Hash Tag.
You can add or remove or change any of the Social Media buttons that you want to change. If you want a button to a different Social Media site then check the help pages on the Social Media site for how to add a Share link. You then need to edit the Sprite image file and change the Sprite image for your new Social Media icon image.
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