Dear sirs, I shoud try to change the html output of your component via template/layout overrides, so that the the link (of an article preview in the status/share panel) gets a class name.
I think the part of code which I should change is this:

<article class="joms-stream-fetch-content" style="margin-left:0; padding-top:0">
<a <?php echo $anchorAttr; ?>><?php echo $attachment->title; ?></a>

Hi.

Just do an template override just like for any other file of that kind in Joomla!.

Copy file ROOT/components/com_community/templates/default/activities.stream.php to ROOT/templates/your-template/html/com_community (if you don't have "html" or "com_community" folders, feel free to create them).

Then edit file in line 175 and add class to anchor.

But in some cases you don't need to have specific class. You can select certain element without a class just using type of element e.g

.joms-stream-box .span4 a

Thank you for your reply, but can you help me to transform that code.
Because I was told the link should gets a class name and now that code is not in this way.
Thank you

HI.

No problem, please, edit your first post and add FTP credentials to corresponding boxes.
Then update this thread so I'll know.