After added appstoreurl many apps and categories are gone


I told my ownCloud 9.1.5 (stable) to use:
'appstoreurl' => '',
wanted to update my calendar, and since then, even though I removed this option from config.php, I do not have categories under Apps, only Enabled and Not Enabled.
Would you know how to revert, fix it?
thanks, L.

I think i have read somewhere that got shut down a few days ago so you probably need to keep that appstoreurl in your config to use the new