The toolbar button to insert a cyrillic capital letter <a href="https://en.wikipedia.org/wiki/Decimal_I_(Cyrillic)" class="extiw" title="en:Decimal I (Cyrillic)">decimal i</a>.
<a href="//commons.wikimedia.org/wiki/User:Sergey_kudryavtsev" title="User:Sergey kudryavtsev">Sergey Kudryavtsev</a> (derivative work) and <a href="//commons.wikimedia.org/wiki/User:Tgr" title="User:Tgr">Tgr</a> (original image)
2010-10-15
self work based on <a href="//commons.wikimedia.org/wiki/File:Button_base.png" title="File:Button base.png">File:Button base.png</a>