Adding Joomla! 4 support for themes

Themes designed to Joomla! 3 do not work in Joomla! 4 without some changes. This document helps you to add Joomla! 4 support to your themes.

NOTE: Joomla! 4 support in Gantry is still work in progress!

Updating theme files to make the theme to run in Joomla! 4.0

Joomla! 4 has made some changes to the templates, which means that also Gantry Themes need to be adjusted to make them to work in the latest Joomla!

Update theme initialization to work in Joomla! 4.0 (please copy updated includes, fields and html folders to your theme!)
Update theme installation to work in Joomla! 4.0 (please copy or update install.php in your theme!)
Update page templates to work in Joomla! 4.0 (please copy or update component.php, error.php, index.php, offline.php in your theme!)
Update SCSS files:
- fadeout($x, n%) to fade-out($x, 0.n)
- transparentize($x, n%) to transparentize($x, 0.n)

Note that Joomla 4 removes support for:

Those still work, but I recommend those to be removed from the themes.