An Anno Fabri tag, hover it for the moment it stands for. The small italic (af) trailing it says what kind of thing the reader is looking at, and leads to Anno Fabri for anyone who does not yet know.
{{af|00Yps}} gives 00Yps (af)The reading is not written out by hand: Module:AF decodes the tag where it stands, era and inverse Feistel and the daylight-saving rule included, so the tooltip cannot drift away from the tag it belongs to. A tag made away from home carries a sixth letter and is understood just as well—{{af|00Q0KX}} gives 00Q0KX (af), which was Nepal.
The other way round is {{afh}}, which writes the moment out and leaves the tag behind: {{afh|00Yps}} gives Tuesday 18 August (2026), 11:11:01 CEST, the date through {{thisday}} and so linked like any other date of the wiki.
An unreadable tag says so in the tooltip rather than failing: {{af|00Q0K7}} gives 00Q0K7 (af), digits being reserved.
The tint and the blue are .af-tag in MediaWiki:Common.css, the trailing parenthesis .af-ref; it is set in EB Garamond through {{garamond}}, held to the tag by a non-breaking space of its own reduced size, and says Anno Fabri on hover.