I must have missed something, but I can't get push notifications working for the Slack app on my Android phone.
In the settings of the app, I've set the Send me push notifications for option to Activity of any kind, with a Push timing of As quickly as possible. I also deactivated the Do not disturb feature just to be sure.
The Slack app is authorized to send me notifications in the OS settings.
What did I forget? Is there a hidden option in the Slack web application that I'm not aware of?
It is a Huawei related issue. The OS is configured to optimize battery use, and therefore forbids Slack to run when the phone is deactivated. For a reason I don't know, some applications are, as soon as they are installed, allowed to run in the background, that's why I got notifications from them (facebook, gmail, whatsapp, snapchat, etc.)
Here is a copy/paste of the procedure to fix the issue (source) :
Step 1: Go to settings --> advanced settings --> battery manager --> protected apps, then find the app you want to see notifications from, and protect it. This is "whitelisting" the app so Huawei's overeager software doesn't shut it down for no reason.
Step 2: Go to settings --> apps --> advanced --> ignore battery optimizations, then find the app and ignore it. Don't be tricked by the misleading wording, "ignoring" the app actually means to let it run, because you're telling the battery optimization function, aka Doze, to "ignore" that app.
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