You can insert inline images to your content. By default, their size is proportional to the font size as their main purpose is to be inserted in line to your content. This is great for inline badges and icons.
There are 3 different sizes of inline images:
Inline size: the default one proportionally sized to the font
Original size: will remain inline but with its original size with a maximum width
Convert to block: this turns an inline image into a block image with its original size
You can add emojis by opening the insert palette, or by clicking twice on an emoji already added to change it.