XF 2.1 Size of smilies

[Sunka]

Some bigger smilies are cropped in menu.
How to fix that?

Example:

 

[Mike]

We limit the height of smilies in this menu. If you're using image smilies (which I assume those are), they should generally be scaled automatically. Sprites will also be limited, though you may need a background size to allow them to scale automatically (probably 100%, though testing may be needed).

 

[Sunka]

though you may need a background size to allow them to scale automatically (probably 100%, though testing may be needed).

Add that in extra.less?

Could you give me exact code for that.
Thank you