It has come to our attention that many users are posting uncensored 18+ screenshots.
Based on the "Rules and Guidelines For Steam" , you cannot post any adult material in the community. That means that no explicit screenshots will be allowed.
Source :
https://support.steampowered.com/kb_article.php?ref=4045-USHJ-3810
"Content Rules
Do not post any content on Steam containing the following:
Porn, inappropriate or offensive content, warez or leaked content or anything else not safe for work"
Thank you for your understanding.