Android App popping up out of nowhere

[hebu]

Since one of the recent updates (August or September maybe?) the Raindrop Android app regularly pops into the foreground suddenly and out of nowhere. I haven't changed any options and I don't know how to prevent it. This is very annoying sometimes, especially when I'm watching a video or reading an article.

I suspect it might happen whenever the app is syncing data. For example, after booting up my tablet, it only takes a short while until the app is popping up.

It's happening on both of my Android devices, my smartphone and my tablet.

Both devices are running Android 8.0.0 (Huawei EMUI) and Raindrop 4.7.3. I am experiencing this at least since Raindrop 4.6.6, maybe even earlier.