I've recently installed Ariva theme.
There seems to be a problem with uploading files/images.
The browse button is either missing or non responsive.
/admin/appearance/settings/md_ariva > Upload Logo Normal > Browse
/admin/structure/block/manage/block/4/configure > IMAGE CONTENT > Upload Logo (No browse button, only Attach button)
Tested on Google Chrome, FireFox.
Also did some testing with jQuery versions - no effect.
No client side cunsole notifications.