If you don't know what Favicon is and what is good for, just use google to find this :)
Favicon in e107:
The header script is looking for the favicon in this order:
1. inside theme folder
2. inside base folder
The automatically inserted favicon should have a name:
favicon.ico
If you need to insert more favicons, you can use meta tags field in main preferences.
if you upload site-button, favicon files are generated without your control:
for all those sizes: 32,16,48,192,167,180
Then this order/priority is used:
- favicon.ico from the theme folder
- generated files (image with name 16x16_favicon.png)
- favicon.ico from root
There is no option to set this behavior off (f.e. to use custom way from the theme.php)