git submodule update --init --recursive in the mediawiki/extensions repository fails with:
... Submodule path 'Widgets': checked out '28b4ebd76df4e75cd045427a98a01c622ffc6130' error: no such remote ref 35480f10e7ce9b0fdaf23d3799d7b79463919b1e Fetched in submodule path 'Widgets/smarty', but it did not contain 35480f10e7ce9b0fdaf23d3799d7b79463919b1e. Direct fetching of that commit failed. ... Failed to recurse into submodule path 'Widgets'