This was seen when the "showtoolbar" preference was enabled from 2006–2010. After then, it was only shown for users who disabled the "enhanced-toolbar" (2010 editor) preference. This editor was removed in MediaWiki 1.32. A similar toolbar is available as a volunteer-supported local gadget at some wikis.
MobileFrontend's original wikitext editor
This was a mobile-specific set of modifications to the 2003 desktop wikitext editor. No longer deployed.