Extensions or Apps Offered by penicillin0
Crx4Chrome includes 2 extensions from the developer penicillin0.
AtCoder Calendar crx 1.1.4 for Chrome
About: Make it easy to add AtCoder contests to your Google Calendar....
Scrapbox List Marker crx 1.7.0 for Chrome New!
About: A chrome extension for Customizing list marker of Scrapbox....