The Formula macro has been bundled in XWiki Standard since version 14.6. Starting with XWiki 14.7RC1, it’s been moved out of XWiki Standard, as a contrib extension that you can install in your wiki.
What’s important to know is that if you’re upgrading to XWiki 14.7+ then the Formula macro will be uninstalled from your wiki automatically and any page using it will display an error message mentioning that the Formula macro is not installed. You’ll need to install the new Formula Macro in version 14.7 or greater. It should appear in the Extension Manager when you search for “Formula Macro”.
See Release Notes for XWiki 14.7 (XWiki.org) for more information.
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