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Settings / Apps / Special App Access / Autostart or Settings / More settings / Applications / Autostart or Manager / App […]
Mobile Manager / PowerMaster / Settings (or Battery-saving options)Disable Clean up in suspend. Disable Auto-deny apps from auto starting.
Enable the padlock icon at an app in the right top corner in the overview of running apps. It’s only then actually running as […]
Settings / Power / Battery optimization Tap on Filter by and set to All Apps Select Gentle Wakeup from the list set to Don’t optimize and […]