Buttons don't show correctly in Firefox|Tweet Like Plusone and Share Plugin|Plugin Support Forum|TECHXT

Hello,

The plugin works great in Chrome and IE, but the buttons don't show correctly on Firefox and the most weird: just on a few posts. 

Buttons on chrome and IE: 

Buttons on Firefox:

I have noted that the problem only happen in Firefox and posts that have no text after the "Read more" tag. As you can see in the second screeshot, the post in the middle(with normal text after the "read more"), the buttons are appearing normal.

Thank you in advance...