admin thems page does not shown

[ahmedfathif2c8]

when hitting Content/Design/Themes

it gets me 

Not registered handle design_theme_listing_data_source

[gaurav_harsh1 · Accepted solution]

Hello @ahmedfathif2c8 ,

After digging something, I think it's issue with your item argument in etc/di.xml, checkout this below blog for reference, it may resolve your problem :

https://www.hungersoft.com/info/not-a-registered-handle-data-source-magento2-admin-grid

[Bhanu Periwal]

Hi @ahmedfathif2c8 

Kindly refer below link for your issue:
https://stackoverflow.com/questions/39763550/magento-2-1-1-admin-content-pages-not-loading-handle-no...

It may help!
Thank you.