I use YMusic to listen to music/audio books, which is an outsider app from xda-developers. When I tried to install an update, I got the message below, as if YouTube is preventing me from installing the app. Here's a Screenshot:
I wanna mention a couple of things:
- This is my personal device, so there's no IT admin
- developer mode is enabled on the device
- It's not the first time I install apps from unknown sources. Usually I have to authorize them during the installation, and this source is authorized
- It's not a rooted device
- it's the latest available version of Android, security update May, 1st 2019
EDIT: After a couple of days, that message didn't appear anymore. Maybe the app had something that conflicts with YouTube, and it was updated? I don't know.