Manual:$wgResourceLoaderLESSImportPaths

ResourceLoader: $wgResourceLoaderLESSImportPaths
Default import paths for LESS modules.
Introduced in version:1.22.0 (Gerrit change 78669; git #b67b9e1b)
Removed in version:1.32.0 (Gerrit change 434046; git #eaf40e6d)
Allowed values:(array)
Default value:"$IP /resources/src/mediawiki.less/"

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Default import paths for LESS modules. LESS files referenced in @import statements will be looked up here first, and relative to the importing file second. To avoid collisions, it's important for the LESS files in these directories to have a common, predictable file name prefix.

Extensions need not (and should not) register paths in $wgResourceLoaderLESSImportPaths. The import path includes the path of the currently compiling LESS file, which allows each extension to freely import files from its own tree.