Wiki creation broken at EE 7.5.10

[Houdini]

Fresh install of EE and wiki, error is:

TypeError Caught
implode(): Argument #2 ($array) must be of type ?array, string given
ee/ExpressionEngine/Service/Model/Column/Serialized/PipeDelimited.php:38

Stack Trace: Please include when reporting this error
#0 ee/ExpressionEngine/Service/Model/Column/Serialized/PipeDelimited.php(38): implode()
#1 ee/ExpressionEngine/Service/Model/Column/SerializedType.php(37): ExpressionEngine\Service\Model\Column\Serialized\PipeDelimited::serialize()
#2 ee/ExpressionEngine/Service/Model/Model.php(712): ExpressionEngine\Service\Model\Column\SerializedType->store()
#3 ee/ExpressionEngine/Service/Model/Model.php(779): ExpressionEngine\Service\Model\Model->typedStore()
#4 ee/ExpressionEngine/Service/Model/Model.php(343): ExpressionEngine\Service\Model\Model->getChangedTypeValues()
#5 ee/ExpressionEngine/Service/Model/Model.php(538): ExpressionEngine\Service\Model\Model->getModified()
#6 ee/ExpressionEngine/Service/Validation/Validator.php(238): ExpressionEngine\Service\Model\Model->getValidationData()
#7 ee/ExpressionEngine/Service/Validation/Validator.php(158): ExpressionEngine\Service\Validation\Validator->prepForObject()
#8 ee/ExpressionEngine/Service/Validation/Validator.php(127): ExpressionEngine\Service\Validation\Validator->_validate()
#9 ee/ExpressionEngine/Service/Model/Model.php(482): ExpressionEngine\Service\Validation\Validator->validate()
#10 user/addons/wiki/mcp.wiki.php(381): ExpressionEngine\Service\Model\Model->validate()
#11 user/addons/wiki/mcp.wiki.php(302): Wiki_mcp->validateWikiSettings()
#12 user/addons/wiki/mcp.wiki.php(188): Wiki_mcp->edit_wiki()
#13 [internal function]: Wiki_mcp->update()
#14 ee/ExpressionEngine/Controller/Addons/Addons.php(1592): call_user_func_array()
#15 ee/ExpressionEngine/Controller/Addons/Addons.php(868): ExpressionEngine\Controller\Addons\Addons->getModuleSettings()
#16 [internal function]: ExpressionEngine\Controller\Addons\Addons->settings()
#17 ee/ExpressionEngine/Core/Core.php(269): call_user_func_array()
#18 ee/ExpressionEngine/Core/Core.php(125): ExpressionEngine\Core\Core->runController()
#19 ee/ExpressionEngine/Boot/boot.php(184): ExpressionEngine\Core\Core->run()
#20 admin.php(139): require_once('...')
#20 admin.php(139): require_once('...')