The project manager of DevriX named Stanko Metodiev share his first-time participation in contributing a patch to WordPress core. As Medtodiev browsing Trac, he found out a bug report with the menu customizer. The change didn’t fix the issue; as a result it submitted a new patch to in order to alter the size by a few more pixels. WordPress lead developer, Helen Hou-Sandi merged into core the change. However, Metodiev persist to contribute to the core and has seven merged patches in WordPress.
Stanko Metodiev stated some advice to new contributors, so if you’re interested to know them kindly check here.