While working on #1743 I found that the [Snooze app](https://code.briarproject.org/akwizgran/snooze) was killed when running overnight on the Redmi Note 7. [Locking the app to the recent apps list](https://code.briarproject.org/briar/briar/-/issues/1743#note_49341) prevented this from happening. We should recommend this during account setup, as we do for Huawei's protected apps and app launch settings. (The user can also [change the app's background setting to "No restrictions"](https://code.briarproject.org/briar/briar/-/issues/1743#note_49269), which is recommended in various places but didn't help in the case of the Snooze app.)